Ups-and-downs of Indian monsoon rainfall likely to increase under warming

PIK June 20, 2013: Day-to-day rainfall in India might become much more variable due to climate change – potentially putting millions of poor farmers and the country’s agricultural productivity at risk. The Indian monsoon is a complex system which is likely to change under future global warming. While it is in the very nature of…

Secrets of Abrupt Climate Shifts revisited

The understanding of the puzzle about what is going on with our climate system and possible implications improved recently. Let’s begin with going back to 2006, here i quote an excerpt from the blog post “Revealed: Secrets of Abrupt Climate Shifts” via RealClimate, describing more robust understanding of the bipolar / see-saw mechanism of the…

Heatwaves blamed on Global Warming

Unusually high frequency points to human influence | NASA climatologist James Hansen made headlines during the US heatwave of 1988, declaring in testimony to Congress and during interviews on prime-time television that a build-up of greenhouse gases was increasing the probability of weather extremes. Now, as much of the United States sizzles through another torrid…

Fresh water from rivers and rain makes hurricanes, typhoons, tropical cyclones 50 percent more intense

An analysis of a decade’s worth of tropical cyclones shows that when hurricanes blow over ocean regions swamped by fresh water, the conditions can unexpectedly intensify the storm. Although the probability that hurricanes will hit such conditions is small, ranging from 10 to 23 percent, the effect is potentially large: Hurricanes can become 50 percent…

Estimating the permafrost-carbon feedback on global warming

A key uncertainty is the fraction of carbon that might be decomposed under anaerobic conditions – resulting potentially in methane emissions to the atmosphere. Given the high warming potential of methane, the overall magnitude of the permafrost-carbon feedback will depend strongly on this fraction. Thawing of permafrost and the associated release of carbon constitutes a…

Last Time Carbon Dioxide Levels Were This High: 15 Million Years Ago

By analyzing the chemistry of bubbles of ancient air trapped in Antarctic ice, scientists have been able to determine the composition of Earth’s atmosphere going back as far as 800,000 years, and they have developed a good understanding of how carbon dioxide levels have varied in the atmosphere since that time. But there has been…

Research closes gap between Warming and CO2 Rise

Feedbacks in the climate system – in which warming is linked to natural CO2 increase, driving further warming – may operate faster than previously thought. ACE CRC: Researchers use Antarctic and Greenland ice cores to examine temperature and CO2 changes during the largest natural climate change in Earth’s recent climate history: the warming out of…

Carbon Dioxide and Climate: A Scientific Assessment

Landmark Report of an Ad Hoc Study Group on Carbon Dioxide and Climate – Woods Hole, Massachusetts to the Climate Research Board, Assembly of Mathematical and Physical Sciences, National Research Council, NATIONAL ACADEMY OF SCIENCES | Washington, D.C. 1979 We have examined the principal attempts to simulate the effects of increased atmospheric CO2 on climate.…

Lesson: Arctic Sea Ice Decline

Jennifer Francis, Rutgers University – assesses the broad topic of the Arctic Sea Ice Decline and explains seasonal impacts. Observations, especially since the 1950’s, explain how the “Arctic Amplification” leads to rapid sea ice changes during the summer month. Much more ridging in North America during the winter. And this affects weather patterns, because a…

Catastrophic sea levels ‘distinct possibility’ this century

A breakthrough study of fluctuations in sea levels the last time Earth was between ice ages, as it is now, shows that oceans rose some three meters in only decades due to collapsing ice sheets. The findings suggest that such an scenario — which would redraw coastlines worldwide and unleash colossal human misery — is…

Potential methane reservoirs beneath Antarctica

We calculate that the sub-Antarctic hydrate inventory could be of the same order of magnitude as that of recent estimates made for Arctic permafrost. Once thought to be devoid of life, the ice-covered parts of Antarctica are now known to be a reservoir of metabolically active microbial cells and organic carbon. The potential for methanogenic…

Hidden rift valley discovered beneath West Antarctica reveals new insight into ice loss

EurekAlert British Antarctic Survey Jul 25 2012: Scientists have discovered a one mile deep rift valley hidden beneath the ice in West Antarctica, which they believe is contributing to ice loss from this part of the continent. Experts from the University of Aberdeen and British Antarctic Survey (BAS) made the discovery below Ferrigno Ice Stream,…

In Ancient Ice, Clues That Scientists Are Underestimating Future Sea Levels

By John Mahoney / Popsci: The skies do strange things at the NEEM camp, a remote ice-drilling and research facility on the northern Greenland ice sheet. Midnight sunshine. Low clouds of sparkling ice crystals known as “diamond dust.” But when rain fell instead of snow last summer, complete with a rainbow arcing over the camp,…