Category: Climate

Our forests

The challenge in deciding what is best for our forests.

As a great many of you already know, we live in a rural area in Southern Oregon. It is a beautiful place and we look out to the East upon Mount Sexton. But locally a great many houses are built on rural sites with the local forest just yards away.

Thus it was with interest that an article on The Conversation website ‘spoke’ to me.

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Fighting every wildfire ensures the big fires are more extreme, and may harm forests’ ability to adapt to climate change

Extreme fires leave forests struggling to recover in a warming world. Mark Kreider

Mark Kreider, University of Montana

In the U.S., wildland firefighters are able to stop about 98% of all wildfires before the fires have burned even 100 acres. That may seem comforting, but decades of quickly suppressing fires has had unintended consequences.

Fires are a natural part of many landscapes globally. When forests aren’t allowed to burn, they become more dense, and dead branches, leaves and other biomass accumulate, leaving more fuel for the next fire. This buildup leads to more extreme fires that are even harder to put out. That’s why land managers set controlled burns and thin forests to clear out the undergrowth.

However, fuel accumulation isn’t the only consequence of fire suppression.

Fire suppression also disproportionately reduces certain types of fire. In a new study, my colleagues and I show how this effect, known as the suppression bias, compounds the impacts of fuel accumulation and climate change.

What happened to all the low-intensity fires?

Most wildfires are low-intensity. They ignite when conditions aren’t too dry or windy, and they can often be quickly extinguished.

The 2% of fires that escape suppression are those that are more extreme and much harder to fight. They account for about 98% of the burned area in a typical year.

The author and colleagues discuss changing wildfire in Montana and Idaho’s Bitterroot Mountains. By Mark Kreider.

In other words, trying to put out all wildfires doesn’t reduce the total amount of fire equally – instead, it limits low-intensity fires while extreme fires still burn. This effect is worsened by climate change.

Too much suppression makes fires more severe

In our study, we used a fire modeling simulation to explore the effects of the fire suppression bias and see how they compared to the effects of global warming and fuel accumulation alone.

Fuel accumulation and global warming both inherently make fires more severe. But over thousands of simulated fires, we found that allowing forests to burn only under the very worst conditions increased fire severity by the same amount as more than a century’s worth of fuel accumulation or 21st-century climate change.

The suppression bias also changes the way plants and animals interact with fire.

By removing low-intensity fires, humans may be changing the course of evolution. Without exposure to low-intensity fires, species can lose traits crucial for surviving and recovering from such events.

After extreme fires, landscapes have fewer seed sources and less shade. New seedlings have a harder time becoming established, and for those that do, the hotter and drier conditions reduce their chance of survival.

In contrast, low-intensity fires free up space and resources for new growth, while still retaining living trees and other biological legacies that support seedlings in their vulnerable initial years.

By quickly putting out low-intensity fires and allowing only extreme fires to burn, conventional suppression reduces the opportunities for climate-adapted plants to establish and help ecosystems adjust to changes like global warming.

Firefighters keep watch for smoke from a fire tower in the Coeur d’Alene National Forest, Idaho, in 1932. Forest Service photo by K. D. Swan

Suppression makes burned area increase faster

As the climate becomes hotter and drier, more area is burning in wildfires. If suppression removes fire, it should help slow this increase, right?

In fact, we found it does just the opposite.

We found that while conventional suppression led to less total area burning, the yearly burned area increased more than three times faster under conventional suppression than under less aggressive suppression efforts. The amount of area burned doubled every 14 years with conventional fire suppression under simulated climate change, instead of every 44 years when low- and moderate-intensity fires were allowed to burn. That raises concerns for how quickly people and ecosystems will have to adapt to extreme fires in the future.

Two charts show fire area increasing faster in a warming climate climate under conventional fire suppression.
With conventional fire suppression, the average fire size will increase faster as the planet warms than it would under a less aggressive approach. Mark Kreider

The fact that the amount of area burned is increasing is undoubtedly driven by climate change. But our study shows that the rate of this increase may also be a result of conventional fire management.

The near total suppression of fires over the last century means that even a little additional fire in a more fire-prone future can create big changes. As climate change continues to fuel more fires, the relative increase in area burned will be much bigger.

This puts more stress on communities as they adapt to increased extreme wildfires, from dealing with more wildfire smoke to even changing where people can live.

A way forward

To address the wildfire crisis, fire managers can be less aggressive in suppressing low- and moderate-intensity fires when it is safe to do so. They can also increase the use of prescribed fire and cultural burning to clear away brush and other fuel for fires.

These low-intensity fires will not only reduce the risk of future extreme fires, but they also will create conditions that favor the establishment of species better suited to the changing climate, thereby helping ecosystems adapt to global warming.

Coexisting with wildfire requires developing technologies and approaches that enable the safe management of wildfires under moderate burning conditions. Our study shows that this may be just as necessary as other interventions, such as reducing the number of fires unintentionally started by human activities and mitigating climate change.

Mark Kreider, Ph.D. Candidate in Forest and Conservation Science, University of Montana

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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The article makes a great deal of sense and presents a solution that may not be our first thought. But especially the message is fundamentally important, and please watch the video because it very clearly presents the benefits of the solution.

So we want more low-intensity fires! Please! Or to say it another way, we want more prescribed fires.

Water, water, everywhere, but …

A dramatic article from George Monbiot about water!

I read the latest from George Monbiot yesterday morning and was startled. Startled because I hadn’t thought of it before. Startled because here in Merlin, Southern Oregon we have had so much rain since the beginning of November, 2023 that our acres are swimming in the wet. Startled since that time also our Bummer Creek, which flows across our land, has been at record depths.

But this report is incredibly important and I wanted to share it with you, as I have Geo. Monbiot’s permission for so doing.

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Dry Run

Posted on11th March 2024

The mega-droughts in Spain and the US are a portent of a gathering global water crisis.

By George Monbiot, published in the Guardian 4th March 2024

There’s a flaw in the plan. It’s not a small one: it is an Earth-sized hole in our calculations. To keep pace with the global demand for food, crop production needs to grow by at least 50% by 2050. In principle, if nothing else changes, this is feasible, thanks mostly to improvements in crop breeding and farming techniques. But everything else is going to change.

Even if we set aside all other issues – heat impacts, soil degradation, epidemic plant diseases accelerated by the loss of genetic diversity – there is one which, without help from any other cause, could prevent the world’s people from being fed. Water.

A paper published in 2017 estimated that to match crop production to expected demand, water use for irrigation would have to increase by 146% by the middle of this century. One minor problem. Water is already maxed out.

In general, the dry parts of the world are becoming drier, partly through reduced rainfall; partly through declining river flow as mountain ice and snow retreats; and partly through rising temperatures causing increased evaporation and increased transpiration by plants. Many of the world’s major growing regions are now threatened by “flash droughts”, in which hot and dry weather sucks moisture from the soil at frightening speed. Some places, such as the southwest of the US, now in its 24th year of drought, may have switched permanently to a drier state. Rivers fail to reach the sea, lakes and aquifers are shrinking, species living in freshwater are becoming extinct at roughly five times the rate of species that live on land and major cities are threatened by extreme water stress.

Already, agriculture accounts for 90% of the world’s freshwater use. We have pumped so much out of the ground that we’ve changed the Earth’s spin. The water required to meet growing food demand simply does not exist.

That 2017 paper should have sent everyone scrambling. But as usual, it was ignored by policymakers and the media. Only when the problem arrives in Europe do we acknowledge that there’s a crisis. But while there is understandable panic about the drought in Catalonia and Andalusia, there’s an almost total failure among powerful interests to acknowledge that this is just one instance of a global problem, a problem that should feature at the top of the political agenda.

Though drought measures have triggered protests in Spain, this is far from the most dangerous flashpoint. The catchment of the Indus river is shared by three nuclear powers – India, Pakistan and China – and several highly unstable and divided regions already afflicted by hunger and extreme poverty. Today, 95% of the river’s dry season flow is extracted, mostly for irrigation. But water demand in both Pakistan and India is growing rapidly. Supply – temporarily boosted by the melting of glaciers in the Himalayas and the Hindu Kush – will, before long, peak and then go into decline.

Even under the most optimistic climate scenario, runoff from Asian glaciers is expected to peak before mid-century, and glacier mass will shrink by about 46% by 2100. Some analysts see water competition between India and Pakistan as a major cause of the repeated conflicts in Kashmir. But unless a new Indus waters treaty is struck, taking falling supplies into account, this fighting could be a mere prelude for something much worse.

There’s a widespread belief that these problems can be solved simply by enhancing the efficiency of irrigation: huge amounts of water are wasted in agriculture. So let me introduce you to the irrigation efficiency paradox. As better techniques ensure that less water is required to grow a given volume of crops, irrigation becomes cheaper. As a result, it attracts more investment, encourages farmers to grow thirstier, more profitable plants, and expands across a wider area. This is what happened, for instance, in the Guadiana river basin in Spain, where a €600m investment to reduce water use by improving the efficiency of irrigation has instead increased it.

You can overcome the paradox through regulation: laws to limit both total and individual water consumption. But governments prefer to rely on technology alone. Without political and economic measures, it doesn’t work.

Nor are other technofixes likely to solve the problem. Governments are planning massive engineering schemes to pipe water from one place to another. But climate breakdown and rising demand ensure that many of the donor regions are also likely to run dry. Water from desalination plants typically costs five or 10 times as much as water from the ground or the sky, while the process requires masses of energy and generates great volumes of toxic brine.

Above all, we need to change our diets. Those of us with dietary choice (in other words, the richer half of the world’s population) should seek to minimise the water footprint of our food. With apologies for harping on about it, this is yet another reason to switch to an animal-free diet, which reduces both total crop demand and, in most cases, water use. The water demand of certain plant products, especially almonds and pistachios in California, has become a major theme in the culture wars, as rightwing influencers attack plant-based diets. But, excessive as the watering of these crops is, more than twice as much irrigation water is used in California to grow forage plants to feed livestock, especially dairy cows. Dairy milk has much higher water demand even than the worst alternative (almond milk), and is astronomically higher than the best alternatives, such as oat or soya milk.

This is not to give all plant products a free pass: horticulture can make massive demands on water supplies. Even within a plant-based diet, we should be switching from some grains, vegetables and fruit to others. Governments and retailers should help us through a combination of stronger rules and informative labelling.

Instead, they do the opposite. Last month, at the behest of the EU’s agricultural commissioner, Janusz Wojciechowski, the European Commission deleted from its new climate plan the call to incentivise “diversified” (animal-free) protein sources. Regulatory capture is never stronger than in the food and farming sector.

I hate to pile yet more on to you, but some of us have to try to counter the endless bias against relevance in politics and most of the media. This is yet another of those massive neglected issues, any one of which could be fatal to peace and prosperity on a habitable planet. Somehow, we need to recover our focus.

http://www.monbiot.com

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Oh dear, oh dear!

One hates to be alarmist and yet Monbiot is a very smart reporter and this is truly important.

Oh dear, oh dear!

Listening to ancient folk

Returning to climate change.

We think that climate change is a relatively recent phenomenon. Wrong! And I am not going to say any more because this post from The Conversation covers it beautifully.

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What ancient farmers can really teach us about adapting to climate change – and how political power influences success or failure

A farmer paddles to his fields on an artificial island among canals, part of an ancient Aztec system known as chinampas, in 2021. AP Photo /Marco Ugarte

Chelsea Fisher, University of South Carolina

Published February, 26th, 2024

In dozens of archaeological discoveries around the world, from the once-successful reservoirs and canals of Angkor Wat in Cambodia to the deserted Viking colonies of Greenland, new evidence paints pictures of civilizations struggling with unforeseen climate changes and the reality that their farming practices had become unsustainable.

Among these discoveries are also success stories, where ancient farming practices helped civilizations survive the hard times.

Zuni farmers in the southwestern United States made it through long stretches of extremely low rainfall between A.D. 1200 and 1400 by embracing small-scale, decentralized irrigation systems. Farmers in Ghana coped with severe droughts from 1450 to 1650 by planting indigenous African grains, like drought-tolerant pearl millet.

Ancient practices like these are gaining new interest today. As countries face unprecedented heat waves, storms and melting glaciers, some farmers and international development organizations are reaching deep into the agricultural archives to revive these ancient solutions.

A canal running through a mountain side with snowy peaks in the background.
An ancient irrigation method used by the Moors involving water channels is being revisited in Spain. Geography Photos/Universal Images Group via Getty Images

Drought-stricken farmers in Spain have reclaimed medieval Moorish irrigation technology. International companies hungry for carbon offsets have paid big money for biochar made using pre-Columbian Amazonian production techniques. Texas ranchers have turned to ancient cover cropping methods to buffer against unpredictable weather patterns.

But grasping for ancient technologies and techniques without paying attention to historical context misses one of the most important lessons ancient farmers can reveal: Agricultural sustainability is as much about power and sovereignty as it is about soil, water and crops.

I’m an archaeologist who studies agricultural sustainability in the past. Discoveries in recent years have shown how the human past is full of people who dealt with climate change in both sustainable and unsustainable ways. Archaeologists are finding that ancient sustainability was tethered closely to politics. However, these dynamics are often forgotten in discussions of sustainability today.

Maya milpa farming: Forest access is essential

In the tropical lowlands of Mexico and Central America, Indigenous Maya farmers have been practicing milpa agriculture for thousands of years. Milpa farmers adapted to drought by gently steering forest ecology through controlled burns and careful woodland conservation.

The knowledge of milpa farming empowered many rural farmers to navigate climate changes during the notorious Maya Collapse – two centuries of political disintegration and urban depopulation between A.D. 800 to 1000. Importantly, later Maya political leaders worked with farmers to keep this flexibility. Their light-handed approach is still legible in the artifacts and settlement patterns of post-Collapse farming communities and preserved in the flexible tribute schedules for Maya farmers documented by 16th century Spanish monks.

Maya farmers and researchers explain milpa farming.

In my book, “Rooting in a Useless Land: Ancient Farmers, Celebrity Chefs, and Environmental Justice in Yucatán,” I trace the deep history of the Maya milpa. Using archaeology, I show how ancient farmers adapted milpa agriculture in response to centuries of drought and political upheaval.

Modern Maya milpa practices began drawing public attention a few years ago as international development organizations partnered with celebrity chefs, like Noma’s René Redzepi, and embraced the concept.

However, these groups condemned the traditional milpa practice of burning new areas of forest as unsustainable. They instead promoted a “no-burn” version to grow certified organic maize for high-end restaurants. Their no-burn version of milpa relies on fertilizers to grow maize in a fixed location, rather than using controlled fire ecology to manage soil fertility across vast forests.

The result restricted the traditional practices Maya farmers have used for centuries. It also fed into a modern political threat to traditional Maya milpa farming: land grabs.

Traditional milpa agriculture requires a lot of forested land, since farmers need to relocate their fields every couple of years. But that need for forest is at odds with hotel companies, industrial cattle ranches and green energy developers who want cheap land and see Maya milpa forest management practices as inefficient. No-burn milpa eases this conflict by locking maize agriculture into one small space indefinitely, instead of spreading it out through the forest over generations. But it also changes tradition.

Maya milpa farmers are now fighting to practice their ancient agricultural techniques, not because they’ve forgotten or lost those techniques, but because neocolonial land privatization policies actively undermine farmers’ ability to manage woodlands as their ancestors did.

Milpa farmers are increasingly left to either adopt a rebranded version of their heritage or quit farming all together – as many have done.

Mexico’s fragile artificial islands: Threats from development

When I look to the work of other archaeologists investigating ancient agricultural practices, I see these same entanglements of power and sustainability.

In central Mexico, chinampas are ancient systems of artificial islands and canals. They have enabled farmers to cultivate food in wetlands for centuries.

The continuing existence of chinampas is a legacy of deep ecological knowledge and a resource enabling communities to feed themselves.

Chinampa techniques use canals and artificial islands. This photo shows one in 1912. Karl Weule, Leitfaden der Voelkerkunde via Wikimedia
A well-maintained farming island among canals near Mexico City.
The chinampas of Xochimilco are a UNESCO world heritage site today, but development expanding from Mexico City has put their survival in danger. Sergei Saint via Flickr, CC BY-ND

But archaeology has revealed that generations of sustainable chinampa management could be overturned almost overnight. That happened when the expansionist Aztec Empire decided to re-engineer Lake Xaltocan for salt production in the 14th century and rendered its chinampas unusable.

Today, the future of chinampa agriculture hinges on a pocket of protected fields stewarded by local farmers in the marshy outskirts of Mexico City. These fields are now at risk as demand for housing drives informal settlements into the chinampa zone.

Andean raised fields: A story of labor exploitation

Traditional Andean agriculture in South America incorporates a diverse range of ancient cultivation techniques. One in particular has a complicated history of attracting revival efforts.

In the 1980s, government agencies, archaeologists and development organizations spent a fortune trying to persuade Andean farmers to revive raised field farming. Ancient raised fields had been found around Lake Titicaca, on the border of Peru and Bolivia. These groups became convinced that this relic technology could curb hunger in the Andes by enabling back-to-back potato harvests with no need for fallowing.

But Andean farmers had no connection to the labor-intensive raised fields. The practice had been abandoned even before the rise of Inca civilization in the 13th century. The effort to revive ancient raised field agriculture collapsed.

A view from a plane shows the outlines where fields were raised.
An aerial photograph shows pre-Colombian raised fields in Bolivia. Umberto Lombardo, University of Bern, Switzerland, CC BY-NC

Since then, more archaeological discoveries around Lake Titicaca have suggested that ancient farmers were forced to work the raised fields by the expansionist Tiwanaku empire during its peak between AD 500 and 1100. Far from the politically neutral narrative promoted by development organizations, the raised fields were not there to help farmers feed themselves. They were a technology for exploiting labor and extracting surplus crops from ancient Andean farmers.

Respecting ancient practices’ histories

Reclaiming ancestral farming techniques can be a step toward sustainable food systems, especially when descendant communities lead their reclamation. The world can, and I think should, reach back to recover agricultural practices from our collective past.

But we can’t pretend that those practices are apolitical.

The Maya milpa farmers who continue to practice controlled burns in defiance of land privatizers understand the value of ancient techniques and the threat posed by political power. So do the Mexican chinampa farmers working to restore local food to disenfranchised urban communities. And so do the Andean farmers refusing to participate in once-exploitive raised field rehabilitation projects.

Depending on how they are used, ancient agricultural practices can either reinforce social inequalities or create more equitable food systems. Ancient practices aren’t inherently good – it takes a deeper commitment to just and equitable food systems to make them sustainable.

Chelsea Fisher, Assistant Professor of Anthropology, University of South Carolina

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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We like to think that the changing climate is a modern phenomenon but this article shows it is not. That sentence by Chelsea Fisher offers a route out of the present situation: “The world can, and I think should, reach back to recover agricultural practices from our collective past.”

Keep it Simple – Live the Dream

A guest post from a friend of many years!

Bob Derham is someone I met many years ago, when I was living on my yacht in Larnaca, Cyprus, and I can do no better than to repeat what I wrote in my autobiography.

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I negotiated what I thought was a good deal and sold the company. Inevitably I resigned from what was now not my company; it was the end of November in the year of 1988.

In Tollesbury, I had my annual tax returns done by Peter Michael, also living in the village. Peter was an accountant who also taught accountancy at the nearby Essex University. I saw Peter and we discussed the recent agreement for the sale of the business.

“Paul, there is not a lot you can do, to be honest. You will be liable in broad terms for the tax in the difference between the opening price and the closing price. In your case the opening price was near enough zero and the closing price…” Peter did not need to finish the sentence. I got the picture and stood up to leave. Just has I was going out of the room, Peter added: “Unless you can leave the country before April 15th next year, and stay away for a minimum of four tax years. In other words, leave before April 15th, 1989.”

I walked home from Peter Michael’s house that November, 1988 with the advice I had been given ringing in my ears. I would worry about the tax implications in a day or two. But once again fate intervened.

I was a subscriber to the boating magazine Practical Boat Owner (PBO). In a late 1988 issue I read in the classifieds:

Songbird of Kent – Tradewind 33

Great opportunity to purchase a long-distance ocean yacht designed by John Rock for sea-kindly short-handed sailing.

Well kitted out, continually updated and maintained Songbird of Kent is the yacht for you if you dream of blue waters and serious long distance cruising.

Lying Larnaca, Cyprus.

I knew about Tradewind yachts, was familiar with John Rock. (As the designer of Tradewind yachts he had been featured several times in Practical Boat Owner magazine), and knew how many of his yachts had made world circumnavigations, and, finally, I deserved a holiday. I arranged to go out to Larnaca as soon as I could.

About a week later I caught a flight to Larnaca International Airport; upon arriving I rented a car and drove the few miles to the Marina.

The yacht was easy to find as it was out of the water. I met the owners, Michael and Betty Hughes, who were still living onboard Songbird of Kent. They explained why they were selling. Simply because, as Michael put it, they had been living on the boat for many years and it was time to return to their native Wales. Songbird had been extensively cruised the length of the Mediterranean Sea using Larnaca Marina as the base.

I quietly inspected the boat. Because it was lifted out viewing the boat in detail was much easier than had it still been floating. It was in good condition; very good condition in fact. Then I climbed up the ladder and entered the boat. Again I found everything that I expected, and more. It was clear to me that Michael and Betty had had the boat as their home and, consequently, everything was in order. Or to use the phrase; shipshape and Bristol fashion!

I excused myself, left the yacht and went and sat on a nearby seawall. I wanted to think. To be honest, it was pretty easy thinking. I loved the boat; it was a purchase I could afford, and if everything went to plan and I left the UK before April 15th, 1989, and stayed away for four tax years, there would be no UK tax to pay on the sale of my company Dataview. Nothing: Nada!

So that is exactly what I did!

I went back to Songbird, where Michael and Betty were still sitting in the cockpit, and told them I would buy it. They drew up a contract there and then and I signed it!

My autobiography

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Here is Bob’s story:

Paul and I first met in 1992, when I was working as a contract pilot on the BAC 1-11 for Cyprus Airways.

My last flying post was down in New Zealand, a wonderful place to be, with it’s natural beauty, and lack of aggression and oppression. The joy of life is set around being outdoors, so road trips, camping, sailing, and skiing all feature, but less on big houses, and possessions.

Although I have travelled widely in my career, I now want a simple life, and that amounts to being free of ties to a property, such that all I really need is a warm, dry place to sleep, a suitable place to prepare food, and a place to relax, it is no longer about the big house, which brings it’s own issues, and expenses.

Following on from my time living on Paul’s boat, I was then drawn to living on a boat. I owned a smaller Westerley Centaur, for a few years, and even though small, I had a very happy time when I lived on that. It was down in Lymington, a small market town on the south coast of England opposite Yarmouth, on the Isle of Wight, that I kept my first boat.

The reason for this was simple 🙂

One of the interesting people I met in Cyprus was a man called Les Powles. Paul and I would regularly go out and have a mezze in a side street of Larnaca. Les would be very easy company, and found fun in the most silly situations. I was invited to call by on his boat any time, and have a “ cuppa”  What I was intrigued with onboard was a picture of the globe, but cut in half, and opened up. There were a series of lines around the world. I asked Les what this was. His reply was “It’s where I have been when sailing round the world.“
So why I asked are their three lines ?
“Because I have done it three times!“

Les was a most unusual character in that he had started building his boat in 1970. It took him 5 years to complete, and apart from a few short sea trials, Les actually had no other sailing experience, but in 1975, with barely enough rice and water onboard, he headed west. Actually he had intended to go to the Caribbean, but he had applied the variation to his navigation the wrong way, and made land fall 1500 miles from his intended destination. Les only died last year, 96, and his home had been his boat for all those years.

It’s that bit that has been the big thing for me.

Having a home has been ongoing hassle, the fun and enjoyment has been removed, because you are in a trap.
It is important to have a home, but I started to question the point of having a physical building. That brings all the ongoing costs and expenses, where the authorities can milk you for a lot of money!

I first saw Antoinette, in Lymington, and from the first moment I saw the boat, I knew I could make the boat my “home.”
She went to Southwold in Suffolk, England for a major refit, and so there is a new engine, gearbox, and propeller, replaced decking, and repairs have been carried out to the hull.

Inside, I can stand up, and although only 37 foot long, being beamy, there is a lot of room.
There are double cabins both fore and after, with “heads” (bathrooms). The main cabin and galley is very comfortable. It has a lot of mahogany wood, so looks homely, and the “dog house” (bit in the middle), is a very open useable space, either enclosed when cold and wet, or if the weather permits, opened up to enjoy the sun.

The key is that this is “my home”. 

I can now travel, and go where I like, but I have my home with me. It has heating, but normally when you arrive somewhere, part of the mooring fees offer a shower unit and facilities. I have space to entertain, but above all, I am free of all the ties that we adopt by following the life society offers us as “the norm“.

It is only now that I see the traps that others face, because I can up anchor and head off, and can see where Les Powles got his freedom, and lived his dream.

In the cabin of Antoinette with Finn the dog belonging to Natalie (on the left).

The collie is “Finn”, Natalie’s dog. I think Paul was one of the first to see her when she was born, so 31 years later, Natalie wants to enjoy the alternative life.

As for Finn, he loves it.  Fresh air, plenty going on, and a lot to see.

“Tiny living”, but the release from the way most people live is amazing.

No speeding tickets for me. 🤪

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Thank you, Bob for the story of you and me. That last thirty years have flown by and those years on Songbird of Kent were really special albeit the end of my cruising days were pretty scary.

The imminent climate change crisis

But a positive TED Talk on the situation.

There have been so many disastrous activities on climate change, and I am not belittling them, but it was amazing to come across a TED Talk last Saturday that I watched. But first the speaker, Asmeret Asefaw Berhe, who was born in Asmara, Eritrea. Her bio (in part):

From WikiPedia:

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Asmeret Asefaw Berhe is a soil biogeochemist and political ecologist who is the current Director of the Office of Science at the US Department of Energy. She was previously the Professor of Soil Biogeochemistry and the Ted and Jan Falasco Chair in Earth Sciences and Geology in the Department of Life and Environmental Sciences; University of California, Merced.[1] Her research group worked to understand how soil helps regulate the Earth’s climate.

Advocacy and global impact work

Berhe’s work at the intersection of soil, climate change, and political ecology lends itself well to a number of global issues. During her graduate career, she was a member of the working group that produced the Millennium Ecosystem Assessment, which was called for by the United Nations Secretary Kofi Annan to assess the impact of humans on the environment. She was one of the lead authors on the 2005 report’s chapter on “Drivers of Change in Ecosystem Condition and Services.”[19] The Assessment received the Zayed International Prize for the Environment in 2005.[20]

In 2018, Berhe was selected as part of the inaugural National Academies of Sciences, Engineering, and Medicine New Voices in Sciences, Engineering, and Medicine cohort, as an early career leader working to advance the conversation around key emerging global issues and communicate the evidence base around those challenges.[21]

An advocate for women in science, Berhe is currently a co-Principal Investigator of ADVANCEGeo, which is working to transform the workplace climate of the geosciences to increase retention of women in the field and develop a sustainable model that can be transferred to other scientific domains. Currently, the Earth Science Women’s Network (ESWN), the Association for Women Geoscientists, and the American Geophysical Union (AGU) have partnered to address the issue of sexual harassment in the earth, space and environmental sciences.[22] The program led by Erika Marín-Spiotta and is run with support from a four-year $1.1 million grant from the National Science Foundation.[23]

She currently serves as an advisory board member of 500 Women Scientists, a grassroots organization working to make science open, inclusive, and accessible, and is on the leadership board of the Earth Science Women’s Network.

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Now from the TED Talk, firstly the description:

Part 3 of the TED Radio Hour episode What Lies Beneath.

Earth’s soil can store vast amounts of carbon. Biogeochemist Asmeret Asefaw Berhe says soil could be a powerful tool for fighting climate change – if only we stopped treating it like dirt.

About Asmeret Asefaw Berhe

Asmeret Asefaw Berhe is a soil biogeochemist and President Biden’s nominee to lead the Department of Energy Office of Science. She is a professor of soil biogeochemistry at University of California, Merced. Her research group works to understand how soil helps regulate the earth’s climate.

Berhe’s work exists at the intersection of soil, climate change, and political ecology. During her graduate career, she was a member of the working group that produced the Millennium Ecosystem Assessment, which was called for by the United Nations to assess the impact of humans on the environment.

Berhe received a B.Sc. in Soil and Water Conservation at the University of Asmara in Eritrea. She has an M.Sc. in Political Ecology from Michigan State University and a Ph.D. in Biogeochemistry from University of California, Berkeley.

This segment of the TED Radio Hour was produced by Matthew Cloutier and Sylvie Douglis and edited by Rachel Faulkner and Katie Simon. You can follow us on Facebook @TEDRadioHour and email us at TEDRadioHour@npr.org.

Now that positive TED Talk:

We wish Asmeret the very best of fortune in bringing about these changes.

Looking after our dogs in Winter

Erik Oltad has some great advice.

In our case our (remaining) dogs, Oliver and Cleopatra, are able to go outside but still remain on our land. But plenty of dog owners are not in such a privileged position and need to take their dogs on public pavements and the like.

Thus for all you dog owners in that position then Erik’s advice is for you.

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Dog care below freezing − how to keep your pet warm and safe from cold weather, road salt and more this winter

Dogs get cold in the winter too, but there are things pet owners can do to help them feel comfortable. AP Photo/David Duprey

Erik Christian Olstad, University of California, Davis

Time outside with your dog in the spring, summer and fall can be lovely. Visiting your favorite downtown café on a cool spring morning, going to a favorite dog park on a clear summer evening or going on walks along a river when the leaves are changing color are all wonderful when the weather is favorable. But in much of the country, when winter rolls around, previously hospitable conditions can quickly turn chilly and dangerous for people and pups alike.

Winter brings some unique challenges for dog owners, since dogs still need activity and socialization during colder seasons. Studies have shown that dog owners are almost 50% less likely to walk their dogs when the weather gets cold. Knowing the basics of winter safety is critical to maintaining a healthy lifestyle for your dog.

I am an assistant professor at the University of California Davis School of Veterinary Medicine who weathered polar vortexes with my dog while living in Michigan early in my career. While I’ve since moved to sunny California, I’ve seen how quickly frigid temperatures can turn dangerous for pets.

Breed and age differences

Not all dogs have the same abilities to deal with cold weather. A short-coated dog like a Chihuahua is much more susceptible to the dangers of cold weather than a thick-coated husky. When the weather dips below 40 degrees Fahrenheit (4 degrees Celsius), the well-acclimated husky may be comfortable, whereas the Chihuahua would shiver and be at risk of hypothermia.

Additionally, if your dog is used to warm weather, but you decide to move to a colder region, the dog will need time to acclimate to that colder weather, even if they have a thick coat.

Age also affects cold-weather resilience. Puppies and elderly dogs can’t withstand the chill as well as other dogs, but every dog is unique – each may have individual health conditions or physical attributes that make them more or less resilient to cold weather.

When is my dog too cold?

A small dog wearing a thick, fluffy red coat.
Dog jackets can keep pets warm in the cold. AP Photo/David J. Phillip

Pet owners should be able to recognize the symptoms of a dog that is getting too cold. Dogs will shiver, and some may vocalize or whine. Dogs may resist putting their feet down on the cold ground, or burrow, or try to find warmth in their environment when they are uncomfortable.

Just like people, dogs can get frostbite. And just like people, the signs can take days to appear, making it hard to assess them in the moment. The most common sites for frostbite in dogs are their ears and the tips of their tails. Some of the initial signs of frostbite are skin discoloring, turning paler than normal, or purple, gray or even black; red, blistered skin; swelling; pain at the site; or ulceration.

Other serious signs of hypothermia include sluggishness or lethargy, and if you observe them, please visit your veterinarian immediately. A good rule to live by is if it is too cold for you, it is too cold for your dog.

Getting your dog a sweater or jacket and paw covers can provide them with protection from the elements and keep them comfortable. Veterinarians also recommend closely monitoring your dog and limiting their time outside when the temperature nears the freezing point or drops below it.

Road salt dangers

Road salt that treats ice on streets and sidewalks can also harm dogs. When dogs walk on the salt, the sharp, rough edges of the salt crystals can irritate the sensitive skin on their paws.

A fluffy dog sits in the snow wearing two cloth, polka dot paw covers.
Paw covers for dogs can keep their feet warm and protected from road salt. AP Photo/Jim Cole

Dogs will often lick their feet when they’re dirty, wet or irritated, and if they ingest any salt doing that, they may face GI upset, dehydration, kidney failure, seizures or even death. Even small amounts of pure salt can disrupt critical body functions in dogs.

Some companies make pet-safe salt, but in public it can be hard to tell what type of salt is on the ground. After walking your dog, wash off their feet or boots. You can also keep their paw fur trimmed to prevent snow from balling up or salt collecting in the fur. Applying a thin layer of petroleum jelly or paw pad balm to the skin of the paw pads can also help protect your pet’s paws from irritation.

A snowy sidewalk covered in tiny chunks of salt.
Road salt can be harmful to dogs’ sensitive paws. Stolbovsky/Wikimedia Commons, CC BY-SA

Antifreeze risks

Antifreeze, or ethylene glycol, is in most vehicles to prevent the fluids from freezing when it gets cold out. Some people pour antifreeze into their toilets when away from their home to prevent the water in the toilet from freezing.

Antifreeze is an exceptionally dangerous chemical to dogs and cats, as it tastes sweet but can be deadly when ingested. If a pet ingests even a small amount of antifreeze, the substance causes a chemical cascade in their body that results in severe kidney damage. If left untreated, the pet may have permanent kidney damage or die.

There are safer antifreeze options on the market that use ingredients other than ethylene glycol. If your dog ingests antifreeze, please see your veterinarian immediately for treatment.

When temperatures dip below freezing, the best thing pet owners can do is keep the time spent outside as minimal as possible. Try some indoor activities, like hide-and-seek with low-calorie treats, fetch or even an interactive obstacle course. Food puzzles can also keep your dog mentally engaged during indoor time.

Although winter presents some unique challenges, it can still be an enjoyable and healthy time for you and your canine companion.

Erik Christian Olstad, Health Sciences Assistant Professor of Clinical Veterinary Medicine, University of California, Davis

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Erik’s comments about ethylene glycol (EG), or antifreeze as it more commonly known, and the incredible dangers to dogs EG possesses are vital to understand.

Please, please keep your dogs very safe in Winter! If Erik’s advice helps save even a single dog then me republishing this will have been worthwhile.

Hollywood movie to reality?

Where is the global climate going?

The challenge with writing posts, albeit not so often, about the global environment, especially when I am a non-scientist, is that one relies entirely on the words of others. In the case of a recent article, published by The Conversation, the authors are claimed to be specialists, and I do not doubt their credentials.

The three authors are René van Westen who is a Postdoctoral Researcher in Climate Physics, at Utrecht University, Henk A. Dijkstra who is a Professor of Physics, also at Utrecht University, and Michael Kliphuis, a Climate Model Specialist, again at Utrecht University.

So, here is their article:

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Atlantic Ocean is headed for a tipping point − once melting glaciers shut down the Gulf Stream, we would see extreme climate change within decades, study shows

Too much fresh water from Greenland’s ice sheet can slow the Atlantic Ocean’s circulation. Paul Souders/Stone via Getty Images

René van Westen, Utrecht University; Henk A. Dijkstra, Utrecht University, and Michael Kliphuis, Utrecht University

Superstorms, abrupt climate shifts and New York City frozen in ice. That’s how the blockbuster Hollywood movie “The Day After Tomorrow” depicted an abrupt shutdown of the Atlantic Ocean’s circulation and the catastrophic consequences.

While Hollywood’s vision was over the top, the 2004 movie raised a serious question: If global warming shuts down the Atlantic Meridional Overturning Circulation, which is crucial for carrying heat from the tropics to the northern latitudes, how abrupt and severe would the climate changes be?

Twenty years after the movie’s release, we know a lot more about the Atlantic Ocean’s circulation. Instruments deployed in the ocean starting in 2004 show that the Atlantic Ocean circulation has observably slowed over the past two decades, possibly to its weakest state in almost a millennium. Studies also suggest that the circulation has reached a dangerous tipping point in the past that sent it into a precipitous, unstoppable decline, and that it could hit that tipping point again as the planet warms and glaciers and ice sheets melt.

In a new study using the latest generation of Earth’s climate models, we simulated the flow of fresh water until the ocean circulation reached that tipping point.

The results showed that the circulation could fully shut down within a century of hitting the tipping point, and that it’s headed in that direction. If that happened, average temperatures would drop by several degrees in North America, parts of Asia and Europe, and people would see severe and cascading consequences around the world.

We also discovered a physics-based early warning signal that can alert the world when the Atlantic Ocean circulation is nearing its tipping point.

The ocean’s conveyor belt

Ocean currents are driven by winds, tides and water density differences.

In the Atlantic Ocean circulation, the relatively warm and salty surface water near the equator flows toward Greenland. During its journey it crosses the Caribbean Sea, loops up into the Gulf of Mexico, and then flows along the U.S. East Coast before crossing the Atlantic.

Two illustrations show how the AMOC looks today and its weaker state in the future
How the Atlantic Ocean circulation changes as it slows. IPCC 6th Assessment Report

This current, also known as the Gulf Stream, brings heat to Europe. As it flows northward and cools, the water mass becomes heavier. By the time it reaches Greenland, it starts to sink and flow southward. The sinking of water near Greenland pulls water from elsewhere in the Atlantic Ocean and the cycle repeats, like a conveyor belt.

Too much fresh water from melting glaciers and the Greenland ice sheet can dilute the saltiness of the water, preventing it from sinking, and weaken this ocean conveyor belt. A weaker conveyor belt transports less heat northward and also enables less heavy water to reach Greenland, which further weakens the conveyor belt’s strength. Once it reaches the tipping point, it shuts down quickly.

What happens to the climate at the tipping point?

The existence of a tipping point was first noticed in an overly simplified model of the Atlantic Ocean circulation in the early 1960s. Today’s more detailed climate models indicate a continued slowing of the conveyor belt’s strength under climate change. However, an abrupt shutdown of the Atlantic Ocean circulation appeared to be absent in these climate models. https://www.youtube.com/embed/p4pWafuvdrY?wmode=transparent&start=0 How the ocean conveyor belt works.

This is where our study comes in. We performed an experiment with a detailed climate model to find the tipping point for an abrupt shutdown by slowly increasing the input of fresh water.

We found that once it reaches the tipping point, the conveyor belt shuts down within 100 years. The heat transport toward the north is strongly reduced, leading to abrupt climate shifts.

The result: Dangerous cold in the North

Regions that are influenced by the Gulf Stream receive substantially less heat when the circulation stops. This cools the North American and European continents by a few degrees.

The European climate is much more influenced by the Gulf Stream than other regions. In our experiment, that meant parts of the continent changed at more than 5 degrees Fahrenheit (3 degrees Celsius) per decade – far faster than today’s global warming of about 0.36 F (0.2 C) per decade. We found that parts of Norway would experience temperature drops of more than 36 F (20 C). On the other hand, regions in the Southern Hemisphere would warm by a few degrees.

Two maps show US and Europe both cooling by several degrees if the AMOC stops.
The annual mean temperature changes after the conveyor belt stops reflect an extreme temperature drop in northern Europe in particular. René M. van Westen

These temperature changes develop over about 100 years. That might seem like a long time, but on typical climate time scales, it is abrupt.

The conveyor belt shutting down would also affect sea level and precipitation patterns, which can push other ecosystems closer to their tipping points. For example, the Amazon rainforest is vulnerable to declining precipitation. If its forest ecosystem turned to grassland, the transition would release carbon to the atmosphere and result in the loss of a valuable carbon sink, further accelerating climate change.

The Atlantic circulation has slowed significantly in the distant past. During glacial periods when ice sheets that covered large parts of the planet were melting, the influx of fresh water slowed the Atlantic circulation, triggering huge climate fluctuations.

So, when will we see this tipping point?

The big question – when will the Atlantic circulation reach a tipping point – remains unanswered. Observations don’t go back far enough to provide a clear result. While a recent study suggested that the conveyor belt is rapidly approaching its tipping point, possibly within a few years, these statistical analyses made several assumptions that give rise to uncertainty.

Instead, we were able to develop a physics-based and observable early warning signal involving the salinity transport at the southern boundary of the Atlantic Ocean. Once a threshold is reached, the tipping point is likely to follow in one to four decades.

A line chart of circulation strength shows a quick drop-off after the amount of freshwater in the ocean hits a tipping point.
A climate model experiment shows how quickly the AMOC slows once it reaches a tipping point with a threshold of fresh water entering the ocean. How soon that will happen remains an open question. René M. van Westen

The climate impacts from our study underline the severity of such an abrupt conveyor belt collapse. The temperature, sea level and precipitation changes will severely affect society, and the climate shifts are unstoppable on human time scales.

It might seem counterintuitive to worry about extreme cold as the planet warms, but if the main Atlantic Ocean circulation shuts down from too much meltwater pouring in, that’s the risk ahead.

This article was updated to Feb. 11, 2024, to fix a typo: The experiment found temperatures in parts of Europe changed by more than 5 F per decade.

René van Westen, Postdoctoral Researcher in Climate Physics, Utrecht University; Henk A. Dijkstra, Professor of Physics, Utrecht University, and Michael Kliphuis, Climate Model Specialist, Utrecht University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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I am 79! I like to think that whatever is coming down the wires, so to speak, will be after my death. But that is a cop out for a) I have a son and a daughter who are in their early fifties, b) I have a grandson, my daughter and son-in-law’s young man, who is a teenager, with his birthday next month, and c) I could possibly live for another twenty years.

The challenge is how to bring this imminent catastrophic global change in temperature to the fore. We need a global solution now enforced by a globally respected group of scientists and leaders, and, frankly, I do not see that happening.

All one can do is to hope. Hope that the global community will eschew the present-day extremes of warring behaviour and see the need for change. That is NOW!

So that the Hollywood movie, The Day After Tomorrow, remains a fictional story. And for those that have forgotten the film or who have never seen it, here is a small slice of a Wikipedia report:

The Day After Tomorrow is a 2004 American science fiction disaster film conceived, co-written, directed, co-produced by Roland Emmerich, based on the 1999 book The Coming Global Superstorm by Art Bell and Whitley Strieber, and starring Dennis Quaid, Jake Gyllenhaal, Sela Ward, Emmy Rossum, and Ian Holm. The film depicts catastrophic climatic effects following the disruption of the North Atlantic Ocean circulation, in which a series of extreme weather events usher in climate change and lead to a new ice age.

Wikipedia

And here is a YouTube video:

There we go, folks!

Atmospheric river hitting us in Merlin

The atmospheric river in California is reaching up to Southern Oregon

After we had the thick end of twelve inches of rain in January, February has kept up the downpours; as of yesterday morning we had had 0.52 inches (1.32 cm) for the month and it was still raining. (And 0.8 in at 08:00 this morning.)

Here’s an item from yesterday about the situation in California.

Plus the BBC News had an item on the California flood.

So it seemed opportune to present this article on atmospheric rivers.

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What is an atmospheric river? A hydrologist explains the good and bad of these flood-prone storms and how they’re changing

A satellite image shows a powerful atmospheric river hitting the Pacific Northwest in December 2023. Darker greens are more water vapor. Lauren Dauphin/NASA Earth Observatory

By Qian Cao, University of California, San Diego

A series of atmospheric rivers is bringing the threat of heavy downpours, flooding, mudslides and avalanches to the Pacific Northwest and California this week. While these storms are dreaded for the damage they can cause, they are also essential to the region’s water supply, particularly in California, as Qian Cao, a hydrologist at the University of California, San Diego, explains.

What are atmospheric rivers?

An atmospheric river is a narrow corridor or filament of concentrated water vapor transported in the atmosphere. It’s like a river in the sky that can be 1,000 miles long. On average, atmospheric rivers have about twice the regular flow of the Amazon River.

When atmospheric rivers run up against mountains or run into local atmospheric dynamics and are forced to ascend, the moisture they carry cools and condenses, so they can produce intense rainfall or snowfall. https://www.youtube.com/embed/w3rtYM0HtIM?wmode=transparent&start=0 A satellite view of atmospheric rivers.

Atmospheric rivers occur all over the world, most commonly in the mid-latitudes. They form when large-scale weather patterns align to create narrow channels, or filaments, of intense moisture transport. These start over warm water, typically tropical oceans, and are guided toward the coast by low-level jet streams ahead of cold fronts of extratropical cyclones.

Along the U.S. West Coast, the Pacific Ocean serves as the reservoir of moisture for the storm, and the mountain ranges act as barriers, which is why the western sides of the coastal ranges and Sierra Nevada see so much rain and snow.

Why are back-to-back atmospheric rivers a high flood risk?

Consecutive atmospheric rivers, known as AR families, can cause significant flooding.

The first heavy downpours saturate the ground. As consecutive storms arrive, their precipitation falls on soil that can’t absorb more water. That contributes to more runoff. Rivers and streams fill up. In the meantime, there may be snowmelt due to warm temperatures, further adding to the runoff and flood risk.

California experienced a historic run of nine consecutive atmospheric rivers in the span of three weeks in December 2022 and January 2023. The storms helped bring most reservoirs back to historical averages in 2023 after several drought years, but they also produced damaging floods and debris flows.

An animation shows filaments of water heading toward the coast.
Atmospheric rivers forming over the tropical Pacific Ocean head for the U.S. West Coast. NOAA

The cause of AR families is an active area of research. Compared with single atmospheric river events, AR families tend to be associated with lower atmospheric pressure heights across the North Pacific, higher pressure heights over the subtropics, a stronger and more zonally elongated jet stream and warmer tropical air temperatures.

Large-scale weather patterns and climate phenomena such as the Madden-Julian Oscillation, or MJO, also play an important role in the generation of AR families. An active MJO shift occurred during the early 2023 events, tilting the odds toward increased atmospheric river activity over California.

A truck drives through muddy streets that fill a large section of town. People stand on one small patch of pavement not flooded.
An aerial view shows a flooded neighborhood in the community of Pajaro in central California on March 11, 2023, after a series of atmospheric rivers. Josh Edelson/AFP via Getty Images

A recent study by scientists at Stanford and the University of Florida found that storms within AR families cause three to four times more economic damage when the storms arrive back to back than they would have caused by themselves.

How important are atmospheric rivers to the West Coast’s water supply?

I’m a research hydrologist, so I focus on hydrological impacts of atmospheric rivers. Although they can lead to flood hazards, atmospheric rivers are also essential to the Western water supply. Atmospheric rivers have been responsible for ending more than a third of the region’s major droughts, including the severe California drought of 2012-16.

Atmospheric rivers provide an average of 30% to 50% of the West Coast’s annual precipitation.

They also contribute to the snowpack, which provides a significant portion of California’s year-round water supply.

In an average year, one to two extreme atmospheric rivers with snow will be the dominant contributors to the snowpack in the Sierra Nevada. Together, atmospheric rivers will contribute about 30% to 40% of an average season’s total snow accumulation there.

A dam spillway with a full reservoir behind it.
After several winter storms brought record snowfall to California’s Sierra Nevada in early 2023, Lake Oroville, California’s second-largest reservoir, was at 100% capacity. The previous year, much of the state had faced water restrictions. Justin Sullivan/Getty Images

That’s why my colleagues at the Center for Western Weather and Water Extremes at the Scripps Institution of Oceanography, part of the University of California, San Diego, work on improving atmospheric river forecasts and predictions. Water managers need to be able to regulate reservoirs and figure out how much water they can save for the dry season while still leaving room in the reservoirs to manage flood risk from future storms.

How is global warming affecting atmospheric rivers?

As global temperatures rise in the future, we can expect more intense atmospheric rivers, leading to an increase in heavy and extreme precipitation events.

My research also shows that more atmospheric rivers are likely to occur concurrently during already wet conditions. So, the chance of extreme flooding also increases. Another study, by scientists from the University of Washington, suggests that there will be a seasonal shift to more atmospheric rivers earlier in the rainy season.

There will likely also be more year-to-year variability in the total annual precipitation, particularly in California, as a study by my colleagues at the Center for Western Weather and Water Extremes projects.

Qian Cao, Hydrologist, Center For Western Weather and Water Extremes, University of California, San Diego

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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PBS have also presented an item on what is an atmospheric river. Their article starts:

Forecasters warned of dangerous flooding, heavy mountain snow and a heightened risk of mudslides and avalanches Feb. 4-6, 2024, as a powerful atmospheric river took aim at California. It’s the latest in a series of atmospheric rivers to bring extreme rainfall to the West Coast.

Qian Cao

I sense many things are changing and the challenge is not to let one’s imagination go into overdrive.

An inspiring TED Talk

Hannah Ritchie raises a very important question.

I was born in London before the end of World War II and to a great extent my upbringing was in the times of yesterday. But the world has moved on in many, many ways. It is too easy to say that we live in very strange times.

Thus it was enlightening to come across this talk, under the TED Talks banner, quite recently. I have great pleasure in sharing it with you. Plus, Hannah’s website is here. (From which I have taken the following words!)

(P.S. The YouTube video is just over thirteen minutes long. It automatically runs into the next video so you will have to stop it yourself.)

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The word “sustainability” gets thrown around a lot these days. But what does it actually mean for humanity to be sustainable? Environmental data scientist Hannah Ritchie digs into the numbers behind human progress across centuries, unpacking why the conventional understanding of sustainability is misleading and showing how we can be the first generation of humans to actually achieve it.

Why you should listen

Hannah Ritchie is deputy editor and research lead at Our World in Data, an online publication making data and research on the world’s largest problems accessible and understandable for non-experts. She is a senior researcher at the University of Oxford, where she studies how environmental issues intersect with others like poverty, global health and education. She has also done extensive research into the question of how to feed everyone in the world a nutritious diet without wrecking the planet. Her work has appeared in The New York Times, The Washington Post, Vox, Wired, BBC, Al Jazeera, The Economist and New Scientist.

In 2022, Ritchie was named Scotland’s Youth Climate Champion. She is also an honorary fellow at the University of Edinburgh and Edinburgh Centre for Carbon Innovation, and a fellow at the Energy for Growth Hub, focused on ending global energy poverty. Her forthcoming book, The First Generation, makes an evidence-based case for why we have a meaningful chance to solve global environmental problems for the first time in human history.

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It is a very inspiring talk; please watch it!

The history of Oxygen!

A fascinating subject.

We take it for granted! Of that I am sure. But the question of how oxygen first came to be built up in our atmosphere is fascinating. There was a recent article written by Elizabeth Swanner, who is Associate Professor of Geology, Iowa State University that was published in The Conversation. It makes for a very interesting read.

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A layered lake is a little like Earth’s early oceans − and lets researchers explore how oxygen built up in our atmosphere billions of years ago

Researchers sample water from various layers to analyze back in the lab. Elizabeth Swanner, CC BY-ND

Elizabeth Swanner, Iowa State University

Little Deming Lake doesn’t get much notice from visitors to Itasca State Park in Minnesota. There’s better boating on nearby Lake Itasca, the headwaters of the Mississippi River. My colleagues and I need to maneuver hundreds of pounds of equipment down a hidden path made narrow by late-summer poison ivy to launch our rowboats.

But modest Deming Lake offers more than meets the eye for me, a geochemist interested in how oxygen built up in the atmosphere 2.4 billion years ago. The absence of oxygen in the deep layers of Deming Lake is something this small body of water has in common with early Earth’s oceans.

On each of our several expeditions here each year, we row our boats out into the deepest part of the lake – over 60 feet (18 meters), despite the lake’s surface area being only 13 acres. We drop an anchor and connect our boats in a flotilla, readying ourselves for the work ahead.

Smooth lake with boats in the distance against woodsy shoreline
Researchers’ boats on Deming Lake. Elizabeth Swanner, CC BY-ND

Deming Lake is meromictic, a term from Greek that means only partially mixing. In most lakes, at least once a year, the water at the top sinks while the water at the bottom rises because of wind and seasonal temperature changes that affect water’s density. But the deepest waters of Deming Lake never reach the surface. This prevents oxygen in its top layer of water from ever mixing into its deep layer.

Less than 1% of lakes are meromictic, and most that are have dense, salty bottom waters. Deming Lake’s deep waters are not very salty, but of the salts in its bottom waters, iron is one of the most abundant. This makes Deming Lake one of the rarest types of meromictic lakes.

man seated in small boat wearing gloves injecting water into a collection tube
Postdoc researcher Sajjad Akam collects a water sample for chemical analysis back in the lab. Elizabeth Swanner, CC BY-ND

The lake surface is calm, and the still air is glorious on this cool, cloudless August morning. We lower a 2-foot-long water pump zip-tied to a cable attached to four sensors. The sensors measure the temperature, amount of oxygen, pH and amount of chlorophyll in the water at each layer we encounter. We pump water from the most intriguing layers up to the boat and fill a myriad of bottles and tubes, each destined for a different chemical or biological analysis.

My colleagues and I have homed in on Deming Lake to explore questions about how microbial life adapted to and changed the environmental conditions on early Earth. Our planet was inhabited only by microbes for most of its history. The atmosphere and the oceans’ depths didn’t have much oxygen, but they did have a lot of iron, just like Deming Lake does. By investigating what Deming Lake’s microbes are doing, we can better understand how billions of years ago they helped to transform the Earth’s atmosphere and oceans into what they’re like now.

Layer by layer, into the lake

Two and a half billion years ago, ocean waters had enough iron to form today’s globally distributed rusty iron deposits called banded iron formations that supply iron for the modern global steel industry. Nowadays, oceans have only trace amounts of iron but abundant oxygen. In most waters, iron and oxygen are antithetical. Rapid chemical and biological reactions between iron and oxygen mean you can’t have much of one while the other is present.

The rise of oxygen in the early atmosphere and ocean was due to cyanobacteria. These single-celled organisms emerged at least 2.5 billion years ago. But it took roughly 2 billion years for the oxygen they produce via photosynthesis to build up to levels that allowed for the first animals to appear on Earth.

water concentrated on a filter looks pale green
Chlorophyll colors water from the lake slightly green. Elizabeth Swanner, CC BY-ND

At Deming Lake, my colleagues and I pay special attention to the water layer where the chlorophyll readings jump. Chlorophyll is the pigment that makes plants green. It harnesses sunlight energy to turn water and carbon dioxide into oxygen and sugars. Nearly 20 feet (6 meters) below Deming’s surface, the chlorophyll is in cyanobacteria and photosynthetic algae, not plants.

But the curious thing about this layer is that we don’t detect oxygen, despite the abundance of these oxygen-producing organisms. This is the depth where iron concentrations start to climb to the high levels present at the lake’s bottom.

This high-chlorophyll, high-iron and low-oxygen layer is of special interest to us because it might help us understand where cyanobacteria lived in the ancient ocean, how well they were growing and how much oxygen they produced.

We suspect the reason cyanobacteria gather at this depth in Deming Lake is that there is more iron there than at the top of the lake. Just like humans need iron for red blood cells, cyanobacteria need lots of iron to help catalyze the reactions of photosynthesis.

A likely reason we can’t measure any oxygen in this layer is that in addition to cyanobacteria, there are a lot of other bacteria here. After a good long life of a few days, the cyanobacteria die, and the other bacteria feed on their remains. These bacteria rapidly use up any oxygen produced by still photosynthesizing cyanobacteria the way a fire does as it burns through wood.

We know there are lots of bacteria here based on how cloudy the water is, and we see them when we inspect a drop of this water under a microscope. But we need another way to measure photosynthesis besides measuring oxygen levels.

Long-running lakeside laboratory

The other important function of photosynthesis is converting carbon dioxide into sugars, which eventually are used to make more cells. We need a way to track whether new sugars are being made, and if they are, whether it’s by photosynthetic cyanobacteria. So we fill glass bottles with samples of water from this lake layer and seal them tight with rubber stoppers.

We drive the 3 miles back to the Itasca Biological Station and Laboratories where we will set up our experiments. The station opened in 1909 and is home base for us this week, providing comfy cabins, warm meals and this laboratory space.

In the lab, we inject our glass bottle with carbon dioxide that carries an isotopic tracer. If cyanobacteria grow, their cells will incorporate this isotopic marker.

We had a little help to formulate our questions and experiments. University of Minnesota students attending summer field courses collected decades worth of data in Itasca State Park. A diligent university librarian digitized thousands of those students’ final papers.

My students and I pored over the papers concerning Deming Lake, many of which tried to determine whether the cyanobacteria in the chlorophyll-rich layer are doing photosynthesis. While most indicated yes, those students were measuring only oxygen and got ambiguous results. Our use of the isotopic tracer is trickier to implement but will give clearer results.

woman holds a clear plastic bag aloft, she and man are seated in boat
Graduate students Michelle Chamberlain and Zackry Stevenson about to sink the bottles for incubation in Deming Lake. Elizabeth Swanner, CC BY-ND

That afternoon, we’re back on the lake. We toss an anchor; attached to its rope is a clear plastic bag holding the sealed bottles of lake water now amended with the isotopic tracer. They’ll spend the night in the chlorophyll-rich layer, and we’ll retrieve them after 24 hours. Any longer than that and the isotopic label might end up in the bacteria that eat the dying cyanobacteria instead of the cyanobacteria themselves. We tie off the rope to a floating buoy and head back to the station’s dining hall for our evening meal.

Iron, chlorophyll, oxygen

The next morning, as we wait for the bottles to finish their incubation, we collect water from the different layers of the lake and add some chemicals that kill the cells but preserve their bodies. We’ll look at these samples under the microscope to figure out how many cyanobacteria are in the water, and we’ll measure how much iron is inside the cyanobacteria.

That’s easier said than done, because we have to first separate all the “needles” (cyanobacteria) from the “hay” (other cells) and then clean any iron off the outside of the cyanobacteria. Back at Iowa State University, we’ll shoot the individual cells one by one into a flame that incinerates them, which liberates all the iron they contain so we can measure it.

rowboat with one woman in it on a lake with woodsy shoreline
Biogeochemist Katy Sparrow rows a research vessel to shore. Elizabeth Swanner, CC BY-ND

Our scientific hunch, or hypothesis, is that the cyanobacteria that live in the chlorophyll- and iron-rich layer will contain more iron than cyanobacteria that live in the top lake layer. If they do, it will help us establish that greater access to iron is a motive for living in that deeper and dimmer layer.

These experiments won’t tell the whole story of why it took so long for Earth to build up oxygen, but they will help us to understand a piece of it – where oxygen might have been produced and why, and what happened to oxygen in that environment.

Deming Lake is quickly becoming its own attraction for those with a curiosity about what goes on beneath its tranquil surface – and what that might be able to tell us about how new forms of life took hold long ago on Earth.

Elizabeth Swanner, Associate Professor of Geology, Iowa State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Nothing I can add to this very erudite article. Please read it and be fascinated by the findings.