Science Daily

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.

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.

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.

Norway is dotted with small glaciers and permanent snow patches that contain all sorts of archaeological treasures, from ancient shoes to 5000-year-old arrowheads. But climate change has turned up the temperature on these snowfields and they are vanishing at an astonishing rate.

A new study shows that undersea volcanoes flare up on strikingly regular cycles, ranging from two weeks to 100,000 years -- and, that they erupt almost exclusively during the first six months of each year. The pulses -- apparently tied to short- and long-term changes in earth's orbit, and to sea levels -- may help trigger natural climate swings.

Geologists once thought that, until about 18,000 years ago, a mammoth glacier covered the top two-thirds of Ireland. Recently, however, they found evidence that it wasn't just the top two-thirds: The Irish glacier was much larger, completely engulfing the country and extending far offshore.

Natural seepage of methane offshore the Arctic archipelago Svalbard has been occurring periodically for at least 2.7 million years. Major events of methane emissions happened at least twice during this period, according to a new study.

A recent study determined that heavy rainfall events have become more frequent over the last 50 years on Hawai'i Island. For instance, a rare storm with daily precipitation of nearly 12 inches, occurring once every 20 years by 1960, has become a rather common storm event on the Big Island of Hawai'i -- returning every 3-5 years by 2009.

New evidence showing the level of atmospheric carbon dioxide millions of years ago supports recent climate change predictions from the Intergovernmental Panel on Climate Change.