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Scientists have found new data on the weather in the Mediterranean basin over the course of the past 20.000 years thanks to the chemical composition of sediments deposited in its seabed.

Historic submarine and modern satellite records show that average ice thickness in the central Arctic Ocean dropped by 65 percent from 1975 to 2012. September ice thickness, when the ice cover is at a minimum, dropped by 85 percent.

A study of how climate change has affected emperor penguins over the last 30,000 years found that only three populations may have survived during the last ice age, and that the Ross Sea in Antarctica was likely the refuge for one of these populations. The Ross Sea is likely to have been a shelter for emperor penguins for thousands of years during the last ice age, when much of the rest of Antarctica was uninhabitable due to the amount of ice. The findings suggest that while current climate conditions may be optimal for emperor penguins, conditions in the past were too extreme for large populations to survive.

The activity of the Sun is an important factor in the complex interaction that controls our climate. New research now shows that the impact of the Sun is not constant over time, but has greater significance when the Earth is cooler.

Using recently released Royal Navy submarine data, researchers have investigated the nature of turbulence in the ocean beneath the Arctic sea-ice. Recent decreases in Arctic sea ice may have a big impact on the circulation, chemistry and biology of the Arctic Ocean, due to ice-free waters becoming more turbulent. By revealing more about how these turbulent motions distribute energy within the ocean, the findings from this study provide information important for accurate predictions of the future of the Arctic Ocean.

The sea-level rise scenarios of the Intergovernmental Panel on Climate Change (IPCC) do not necessarily provide the right information for high-risk coastal decision-making and management, according to new research. A commentary warns that the IPCC scenarios are often inappropriate or incomplete for the management of high-risk coastal areas as they exclude the potential for extreme sea-level rises. This missing information is also crucial for a number of policy processes, such as discussions by G7 countries to establish climate insurance policies and allocations of adaptation funding by the Green Climate Funds.

How was human evolution and migration influenced by past changes in climate? Researchers hope to find out.

A unique study of frozen ice cores from the Tibetan Himalayas has shown that international agreements on phasing out the use of toxic persistent organic pollutants are working. "Chemical residues are carried thousands of miles on the prevailing winds and deposited in the ice. Ice cores are very effective barometers of pollution over time as ice is laid down over the decades," authors explain.

Telling time is important to scientists who work in the deep past. As humans, we find it difficult to tell time beyond the scale of a lifetime. Last week runs into last month. Those months build up into years and decades. To those of us born in the 1970s, 25 years ago (1990—pre-internet) is half […]

The first comprehensive map of the topsy-turvy climate in the western U.S, 21,000 years ago has been developed by researchers. They focus on when the Southwest was wet and the Northwest was dry, testing it to improve the global climate models that have been developed to predict how precipitation patterns will change in the future.

This blog has been *sleeping* for a few months. Why, you might ask dear reader? Well…the last few months could best be described as schizophrenic. The projects that we’ve been working on are pretty diverse, and they’ve all been progressing, more or less, synchronously. So stay tuned for more details. In the meantime, here’s a rundown of what’s in the hopper.

1. Mammoths and mastodons. Our extinction project is in its last year. The dates are rolling in and we have some very interesting results. We’ve narrowed down the error estimate around the actual time of mastodon extinction to ~250 years. They blip out in the Midwest just as the Younger Dryas, a return to glacial conditions, is getting underway ~12.9 ka. Although mammoths are probably extirpated at about the same time (the last mammoth dates are just a few hundred years earlier than the last mastodon dates), their pattern of extinction is much different. Mastodons go out with a bang. In the last few hundred years prior to extinctions, mastodons are still distributed widely throughout the Midwest. In fact, many sites dating to this time period have multiple animals in them (including Boney Spring, MO, with ~31 mastodons). Mammoths however, are fewer and farther between by the time the terminal Pleistocene rolls around. Although they are here, shoulder to shoulder with mastodons, they are not present in high numbers.

2. MORE Mammoths and Mastodons. Although our project is focused on the extinction of these beasts, we’ve also been able to document quite a bit of morphological diversity in mammoths and mastodons. What do these patterns mean? Are they due to a complex evolutionary history? Or to local environmental pressures? Are there chronoclines (shape and size changes through time) that might give us insight into adaptive strategies?

3. Even MORE Mammoths and Mastodons…and isotopes. We’ve been tweaking our new micromill technique to drill very tiny holes in mammoth teeth. The importance of this research is that it gives us a seasonal-scale picture of the life of a mammoth over the course of a few years. We can see what it was eating and where it was moving (IF it was moving).

4. 3D scanning and printing. In June we received our first 3D printer. In August we received our second. We’ve been working to test the dozens of 3D scans we’ve done over the last year or so. We’re hoping to post them to a gallery soon.

5. Going to the dogs. Illinois is home to one of the most complete records of early dogs in North America. A few years back, we started re-analyzing dog remains from the Koster and Stilwell sites in western Illinois for insight into the lives of these early dogs. I’ll definitely be talking more about them in the next few months.

6. Just batty. Finally, no blog post would be complete without some mention of the bat paleontology that we’ve been working on. Bat guano. Bat bones. Bat ecology.

From mega to micro. Stay tuned for more updates.

C

Precipitation reconstructions are essential for predicting impacts of future climate change and preparing for potential changes in terrestrial environmental conditions. Reliable proxy records of paleoprecipitation, especially from past warm periods, are a valuable tool for assessing and modeling future soil and plant moisture and local water availability. However, current terrestrial proxies are limited in their applications, and as a result, a wide range of paleoenvironments are underrepresented in the geologic record.

Scientists have managed to quantify how the Greenland Ice Sheet reacted to a warm period 8,000-5,000 years ago. Back then temperatures were 2-4 degrees C warmer than they are in the present. Their results are important as we are rapidly closing in on similar temperatures.

Considerable debate surrounds the migration of human populations out of Africa. Two predominant hypotheses concerning the timing contrast in their emphasis on the role of the Arabian interior and its changing climate. In one scenario, human populations expanded rapidly from Africa to southern Asia via the coastlines of Arabia approx. 50,000 to 60,000 years ago. Another model suggests that dispersal into the Arabian interior began much earlier (approx. 75,000 to 130,000 years ago) during multiple phases, when increased rainfall provided sufficient freshwater to support expanding populations.

Recent research has yielded new data on chemical gardens, mysterious formations produced when certain solid salts -- copper sulfate, cobalt chloride -- are added to an aqueous solution of sodium silicate.

Ice and winter floods are important natural disturbances for maintaining species-rich riparian zones along northern watercourses. If the climate becomes warmer this disturbance might be lost. This could potentially lead to a less diverse riparian zone.

A release of carbon dioxide from the deep ocean helped bring an end to the last Ice Age, according to new research. The study shows that carbon stored in an isolated reservoir deep in the Southern Ocean re-connected with the atmosphere, driving a rise in atmospheric CO2 and an increase in global temperatures. The finding gives scientists an insight into how the ocean affects the carbon cycle and climate change.

Sea ice increases in Antarctica do not make up for the accelerated Arctic sea ice loss of the last decades, a new study finds. As a whole, the planet has been shedding sea ice at an average annual rate of 13,500 square miles (35,000 square kilometers) since 1979, the equivalent of losing an area of sea ice larger than the state of Maryland every year.

A massive canyon that is home to Europe's most powerful waterfall was created in a matter of days by extreme flooding, new research reveals.

Researchers have uncovered the earliest evidence of widespread, human-produced air pollution in South America -- from the Spanish conquest of the Inca.