A new study shows the Arctic climate system may be more sensitive to greenhouse warming than previously thought, and that current levels of Earth’s atmospheric carbon dioxide may be high enough to bring about significant, irreversible shifts in Arctic ecosystems.
Led by the University of Colorado at Boulder, the international study indicated that while the mean annual temperature on Ellesmere Island in the High Arctic during the Pliocene Epoch 2.6 to 5.3 million years ago was about 34 degrees Fahrenheit, or 19 degrees Celsius, warmer than today, CO2 levels were only slightly higher than present. The vast majority of climate scientists agree Earth is warming due to increased concentrations of heat-trapping atmospheric gases generated primarily by …

Human-driven changes in the earth’s atmospheric composition are likely to alter plant diseases of the future. Researchers predict carbon dioxide will reach levels double those of the preindustrial era by the year 2050, complicating agriculture’s need to produce enough food for a rapidly growing population.
University of Illinois researchers are studying the impact of elevated carbon dioxide, elevated ozone and higher atmospheric temperatures on plant diseases that could challenge crops in these changing conditions.
Darin Eastburn, U of I associate professor of crop sciences, evaluated the effects of elevated carbon dioxide and ozone on three economically important soybean diseases under natural field conditions at the soybean-free air-concentrating enrichment (SoyFACE) facility in Urbana.
The diseases downy mildew, Septoria brown …

U.S. satellite measurements show Arctic sea ice extent in 2009 – the area of the Arctic Ocean covered by floating ice – was the third lowest since satellite measurements were first made in 1979. The ice area at minimum was an increase from the past two years, but still well below the average for the past 30 years.
Arctic sea ice reached its minimum extent around September 12, as shown in the image and video below/above. According to scientists affiliated with the National Snow and Ice Data Center (NSIDC), sea ice coverage dropped to 5.10 million square kilometers (1.97 million square miles) at its minimum. The ice cover was 970,000 square kilometers (370,000 square miles) greater …

A knowledge gap exists in the area of climate research: for decades, scientists have been asking themselves whether, and to what extent man-made aerosols, that is, dust particles suspended in the atmosphere, enlarge the cloud cover and thus curb climate warming. Research has made little or no progress on this issue.
Two scientists from the Max Planck Institute for Meteorology in Hamburg (MPI-M) and the American National Oceanic and Atmospheric Administration (NOAA) report in the journal Nature that the interaction between aerosols, clouds and precipitation is strongly dependent on factors that have not been adequately researched up to now. They urge the adoption of a research concept that will close this gap in the knowledge. (Nature, …

Will all of the ice on Greenland melt and flow out into the sea, bringing about a colossal rise in ocean levels on Earth, as the global temperature rises?
The key concern is how stable the ice cap actually is and new Danish research from the Niels Bohr Institute at the University of Copenhagen can now show the evolution of the ice sheet 11,700 years back in time – all the way back to the start of our current warm period. The results are published in the esteemed journal Nature.
Numerous drillings have been made through both Greenland’s ice sheet and small ice caps near the coast. By analysing every single annual layer in the kilometres long …

Inaction already threatening multi-billion dollar coral reef services and livelihoods of half a billion people
Investing in restoration and maintenance of the Earth’s multi-trillion dollar ecosystems – from forests and mangroves to wetlands and river basins – can have a key role in countering climate change and climate-proofing vulnerable economies.
This is among the central findings of a new climate issues update by The Economics of Ecosystems and Biodiversity (TEEB), a project launched by Germany and the European Commission in response to a proposal by the G8+5 Environment Ministers (Potsdam, Germany 2007) to develop a global study on the economics of biodiversity loss. The study is hosted by the United Nations Environment Programme. The issues update was …

The future of the Earth could rest on potentially dangerous and unproven geoengineering technologies unless emissions of carbon dioxide can be greatly reduced, a new study has found.
The report (published September 1, by the Royal Society, the UK’s national academy of science) found that unless future efforts to reduce greenhouse gas emissions are much more successful than they have been so far, additional action in the form of geoengineering will be necessary to cool the planet. However, the report identified major uncertainties regarding the effectiveness, costs, and environmental impacts of geoengineering technologies.
“Reducing our greenhouse gas emissions is more important than ever,” said coauthor Ken Caldeira of the Carnegie Institution’s Department of Global Ecology, “but even …