Greenhouse gases, which drive global warming, continue to increase and carbon dioxide concentrations reached their highest level ever in 2007, according to a publication released today by the United Nations World Meteorological Organization.

Greenhouse gas emissions of 40 industrialized countries rose by 2.3 per cent between 2000 and 2006, while still about 5 per cent below the 1990 level, according to United Nations figures released today, two weeks before a major review conference on the issue.

The United Nations Food and Agriculture Organization (FAO) warned today that climate change-related disasters such as cyclones, flash floods and droughts are likely to have a serious impact on food production in Pacific island nations, and called for urgent measures to adapt to expected losses.

While many view climate change as a future threat, humanitarians are seeing its impact now. In the last 20 years, the number of recorded disasters has doubled from about 200 to more than 400 per year. Disasters caused by floods are more frequent (from about 50 in 1985 to more than 200 in 2005) and damage larger areas than they did twenty years ago.

Contrary to earlier projections, few developing countries will be able to afford more efficient technologies to reduce greenhouse gas emissions in the next few decades, new research concludes. The study, by the NCAR and the University of Colorado, warns that continuing economic and technological disparities will make it more difficult than anticipated to reduce greenhouse gas emissions, and it underscores the challenges that poorer nations face in trying to adapt to global warming.

Global warming, some have argued, can be reversed with a large-scale "geoengineering" fix, such as having a giant blimp spray liquefied sulfur dioxide in the stratosphere or building tens of millions of chemical filter systems in the atmosphere to filter out carbon dioxide.

Rapidly warming climate is likely to seriously alter crop yields in the tropics and subtropics by the end of this century and, without adaptation, will leave half the world's population facing serious food shortages, new research shows.

Temperature change in the Arctic is happening at a greater rate than other places in the Northern Hemisphere, and this is expected to continue in the future. As a result, glacier and ice-sheet melting, sea-ice retreat, coastal erosion and sea level rise can be expected to continue.

Ever since scientists first proposed that our planet might be experiencing widespread climate change, concerns have been raised about its implications for the spread of arboviruses – viruses carried by arthropods such as mosquitoes, midges and ticks. However, while alterations in temperature and rainfall are important factors in making new territory hospitable to an invading arbovirus, many other forces also play significant parts in new patterns of viral emergence.