This Rob Dunbar is NOT Robin Dunbar the Archaeologist.

Rob Dunbar hunts for data on our climate from 12,000 years ago, finding clues inside ancient seabeds and corals and inside ice sheets. His work is vital in setting baselines for fixing our current climate — and in tracking the rise of deadly ocean acidification.

Continue reading Rob Dunbar: Discovering ancient climates in oceans and ice →

In the 1960s, the whole idea of a “greenhouse effect” was well understood, and assumed to be an important potential factor in climate change. So was glaciation, and the short and medium term future of the Earth’s climate was less clear than compared to now. But the basics were there … C02 was being released into the atmosphere, this could cause a greenhouse effect, and that would warm the earth. Certainly by the early 1980s, it was possible to make some thumb-suck estimates of how much the earth would warm given various assumptions about CO2, and it was not that difficult to see that a lot of fossil carbon was being put into the atmosphere.
Continue reading Science as a Contact Sport by Stephen Schneider →

See the missing bit? That is a 1.5 kilometer retreat of the so-called “calving front” of the glacier.

In truth, this particular sort of even is not that unusual, but what is interesting is that new satellite monitoring capabilities allow researchers to notice these events more or less when they happen, as opposed to during less frequent inspections of satellite imagery.

And, there are some climate-change related features of this event.

Continue reading What was that splash? Oh. Greenland melting. →

Anthropogenic global warming has been suspected for decades, and a simple one paragraph long characterization of the problem 40 years ago was substantially identical to any accurate characterization we might make today. One has to wonder why after 40 years of time we still see headlines telling us that it might, after all, turn out to be true that anthropogenic global warming is real. Indeed, it is a bit disconcerting when the inestimable climate blog RealClimate notes that this is the 35th “Anniversary of Global Warming” as a term in the peer reviewed scientific literature (though I suspect it is older). (See RealClimate’s post on the anniversary for very important details!)

The phenomenon of anthropogenic global warming as a point of policy discussion is older than 35 years. Below is a memo from one White House staffer to another both to eventually become quite famous in their own ways, regarding the “carbon dioxide problem.” You will find a link to a copy of the original, and some context notes for you youn’uns who may not remember the mid 20trh century. Below the fold.
Continue reading 1969 Global Warming White House Memo →

From James at Island of Doubt.

One item is just published in the Journal of Climate. Simply put, the use of some very sophisticated and probably quite trustworthy models suggests that extratropical cyclones (so this means winter storms and such, mainly) will have a good deal more precipitation in them.

In the model …

… There is a small reduction in the number of cyclones but no significant changes in the extremes of wind and vorticity in both hemispheres. … The largest changes are in the total precipitation, where a significant increase is seen. Cumulative precipitation along the tracks of the cyclones increases by some 11% per track … while the extreme precipitation is close to … (some 27%).

In another study not available to me but coming out in the same journal in a few days, the overall effects of climate change are predicted to be much worse than previously thought.

This is based on MIT’s Integrated Global Systems Model, which is a computer simulation of both global economic activity and climatic systems. This mega-simulation was run 400 times using slight variations in input parameters. According to a press release:

The new projections… indicate a median probability of surface warming of 5.2 degrees Celsius by 2100, with a 90% probability range of 3.5 to 7.4 degrees. This can be compared to a median projected increase in the [previous major study, conducted in] 2003 … of just 2.4 degrees. The difference is caused by several factors rather than any single big change. Among these are improved economic modeling and newer economic data showing less chance of low emissions than had been projected in the earlier scenarios. Other changes include accounting for the past masking of underlying warming by the cooling induced by 20th century volcanoes, and for emissions of soot, which can add to the warming effect. In addition, measurements of deep ocean temperature rises, which enable estimates of how fast heat and carbon dioxide are removed from the atmosphere and transferred to the ocean depths, imply lower transfer rates than previously estimated.

Continue reading New Global Warming Predictions: Bad news and really bad news. →