Tag: Carboniferous

Gondolas for New York?

Can we really make sense of the science of climate change?

Those that come to this Blog on a regular basis, and many thanks to you, by the way, will know that, overall, I take the stance that climate change, global warming, etc., etc. is real.  At the very least to me it is reasonably described by the saying that most pilots are familiar with, “If there’s any doubt, there’s no doubt.”  In other words, if something is worrying you don’t hesitate to get your ‘arse’ on the ground.

The planet’s climate systems are incredibly complex and like processes and systems much less complex than the earth’s atmosphere getting to real hard evidence is challenging.  Please accept that my personal position is unchanged; for me there are sufficient signs to suggest that climatic changes may be more likely, than less likely, to substantially harm humankind’s existence on Planet Earth within the next generation.

However, Dan Gomez, my very good Californian friend of 40-plus years, is much more sceptical.  I respect his intellect greatly and, therefore, respect his opinions.  Dan recently sent me a number of documents that raise valid questions.  Over time I want to share these with you and invite anyone who wishes to comment on Learning for Dogs to do so, or even better submit a guest post.

But before going to the first of Dan’s documents, let me share something that was reported by BBC News recently.  It’s this.

New York is a major loser and Reykjavik a winner from new forecasts of sea level rise in different regions.

The Intergovernmental Panel on Climate Change (IPCC) said in 2007 that sea levels would rise at least 28cm (1ft) by the year 2100.

But this is a global average; and now a Dutch team has made what appears to be the first attempt to model all the factors leading to regional variations.

Other researchers say the IPCC’s figure is likely to be a huge under-estimate.

Whatever the global figure turns out to be, there will be regional differences.

That IPCC report may be accessed here and the main website of the IPCC is here.  But even the BBC’s report shows that scientists are still learning more, as time goes on.

Ocean currents and differences in the temperature and salinity of seawater are among the factors that mean sea level currently varies by up a metre across the oceans – this does not include short-term changes due to tides or winds.

So if currents change with global warming, which is expected – and if regions such as the Arctic Ocean become less saline as ice sheets discharge their contents into the sea – the regional patterns of peaks and troughs will also change.

“Everybody will still have the impact, and in many places they will get the average rise,” said Roderik van der Wal from the University of Utrecht, one of the team presenting their regional projections at the European Geosciences Union (EGU) meeting in Vienna.

“But places like New York are going to have a larger contribution than the average – 20% more in this case – and Reykjavik will be better off.”

The news item also contains some fascinating evidence of the influence of gravity from the mass of the polar ice caps.  Read the full article here.

Gondola's for hire in a few year's time?

Now on to one of Dan’s documents.  It is from the website detailing the history of plant fossils of West Virginia.  The document refers to the climate of the carboniferous period.  Here’s how it starts.

West Virginia today is mostly an erosional plateau carved up into steep ridges and narrow valleys, but 300 million years ago, during the Carboniferous Period, it was part of a vast equatorial coastal swamp extending many hundreds of miles and barely rising above sea level. This steamy, tropical quagmire served as the nursery for Earth’s first primitive forests, comprised of giant lycopods, ferns, and seed ferns.

North America was located along Earth’s equator then, courtesy of the forces of continental drift. The hot and humid climate of the Middle Carboniferous Period was accompanied by an explosion of terrestrial plant life. However by the Late Carboniferous Period Earth’s climate had become increasingly cooler and drier. By the beginning of the Permian Period average global temperatures declined by about 10° C.

Interestingly, the last half of the Carboniferous Period witnessed periods of significant ice cap formation over polar landmasses– particularly in the southern hemisphere. Alternating cool and warm periods during the ensuing Carboniferous Ice Age coincided with cycles of glacier expansion and retreat. Coastlines fluctuated, caused by a combination of both local basin subsidence and worldwide sea level changes. In West Virginia a complex system of meandering river deltas supported vast coal swamps that left repeating stratigraphic levels of peat bogs that later became coal, separated by layers of fluvial rocks like sandstone and shale when the deltas were building, and marine rocks like black shales and limestones when rising seas drowned coastlands. Accumulations of several thousand feet of these sediments over millions of years caused heat and pressure which transformed the soft sediments into rock and the peat layers into the 100 or so coal seams which today comprise the Great Bituminous Coalfields of the Eastern U.S. and Western Europe.

One needs to read the full article to properly understand this period of history of the planet.  But it includes revealing diagrams like this one.

Global Temperature and Atmospheric CO2 over Geologic Time

Here’s how it concludes.

What will our climate be like in the future? That is the question scientists are asking and seeking answers to currently. The causes of “global warming” and climate change are today being popularly described in terms of human activities. However, climate change is something that happens constantly on its own. If humans are in fact altering Earth’s climate with our cars, electrical powerplants, and factories these changes must be larger than the natural climate variability in order to be measurable. So far the signal of a discernible human contribution to global climate change has not emerged from this natural variability or background noise.

Understanding Earth’s geologic and climate past is important for understanding why our present Earth is the way it is, and what Earth may look like in the future. The geologic information locked up in the rocks and coal seams of the Carboniferous Period are like a history book waiting to be opened. What we know so far, is merely an introduction. It falls on the next generation of geologists, climatologists, biologists, and curious others to continue the exploration and discovery of Earth’s dynamic history– a fascinating and surprising tale, written in stone.


Truth fears no questions.  ~Unknown