ScienceDaily: Earth & Climate News

Maps of the American West have featured ever darker shades of red over the past two decades. The colors illustrate the unprecedented drought blighting the region. In some areas, conditions have blown past severe and extreme drought into exceptional drought. But rather than add more superlatives to our descriptions, one group of scientists believes it's time to reconsider the very definition of drought.

Using lake sediment in the Tibetan Plateau, a team of researchers was able to show that permafrost at high elevations is more vulnerable than arctic permafrost under projected future climate conditions.

New research into the life and times of a New England salt marsh fundamentally changes our understanding of how salt marshes acquire the sediment that keeps them viable. This research has wide-ranging implications for managing New England's coastline as it struggles to keep up with development, sea-level rise and other environmental impacts.

A new study has documented how the thawing of permafrost submerged underwater at the edge of the Arctic Ocean is affecting the seafloor.

Scientists believe a strategy used to protect popular surfing spots could now be more widely adopted to help preserve endangered coastal environments.

Prolonged droughts and heat waves have negative consequences both for people and the environment. If both of these extreme events occur at the same time, the impacts, in the form of wild fires, tree mortality or crop losses -- to name a few examples -- can be even more severe. Climate researchers have now discovered that, assuming a global temperature increase of two degrees in the course of global warming, the future frequency of these simultaneously occurring extreme events is primarily determined by local precipitation trends. Understanding this is important, since it enables us to improve our risk adaptation to climate change and our assessment of its consequences, according to the researchers.

Researchers warn that permafrost peatlands in Europe and Western Siberia are much closer to a climatic tipping point than previous believed. The frozen peatlands in these areas store up to 39 billion tons of carbon -- the equivalent to twice that stored in the whole of European forests.

Geologists have come up with multiple lines of evidence indicating that the Bushveld Complex in South Africa functioned as a 'big magma tank' in the ancient Earth's crust.

As a result of global warming in the 21st century, the Greenland ice sheet may contribute several meters to sea-level rise in the centuries to come; however, effective climate change mitigation measures will greatly reduce its decay.

Researchers focused on the climate of the Pliocene, over 3 million years ago, the last time Earth has seen concentrations of over 400 PPM CO2 in the atmosphere, similar to today's concentrations. The Pliocene prompts a long-standing question: despite the similarity to the present-day, why were dry areas like the Sahel in Africa and Northern China much wetter and greener in the Pliocene than they are today?

A new study estimates that over the next 30 years, 1.4 million street trees will be killed by invasive insects, costing over 900 million dollars to replace.

There are practical limits to the height at which aerosols may be deployed in the atmosphere to deflect incoming sunlight and countervail global warming. Very high-altitude injections might be more effective, but such climate intervention comes with substantially increased costs and safety risks, according to new research.

Higher lead levels in a mother's blood can increase the chance of her bearing male offspring, according to new research.