Record low in Arctic sea ice caused by global warming, says UN

The World Meteorological Organisation, that tracks the weather on behalf of the 193 countries of the United Nations, confirmed 2012 was the 9th warmest year on record.The annual summary of climate change also warned Arctic sea ice reached its lowest ever level, rainfall increased causing floods around the world and a number of countries experienced drought.Extreme weather events, like Superstorm Sandy in the US and Typhoon Bopha in the Philippines, were linked to climate change.Michel Jarraud, Secretary-General of the WMO, said natural variability - like the La Nina/ El Nino pattern in the Pacific - means global warming will not necessarily make each year successively warmer than the last.
Source:http://www.telegraph.co.uk/earth/environment/climatechange/10033034/Record-low-in-Arctic-sea-ice-caused-by-global-warming-says-UN.html

Global Warming Trends Contribute to Spread of West Nile Virus to New Regions in Europe

May 13, 2013 — Global warming trends have a significant influence on the spread of West Nile Virus to new regions in Europe and neighboring countries, where the disease wasn't present before, according to a new study by the University of Haifa. The study was commissioned by the European Centre for Disease Prevention and Control (ECDC) in Stockholm, which belongs to the European Union. The study found that rising temperatures have a more considerable contribution than humidity, to the spread of the disease, while the effect of rain was inconclusive.

"These results are an additional testament that global warming contributes to the outbreak of mosquito-borne and other temperature-sensitive vector-borne diseases. The indications to this are piling up in different parts around the globe," says Dr. Shlomit Paz, who led this research. These findings were recently published in the online scientific journal, PLoS One.

West Nile Virus is spread by mosquitoes that repeatedly bite infected birds. The potential threat the infection poses to man is the possibility of causing irreversible brain damage or even death through encephalitis or meningitis. The elderly and people with weak immune systems are most susceptible.

The research, conducted by a team from the University of Haifa led by Dr. Shlomit Paz, also included Dr. Dan Malkinson and Gil Tzioni from the Department of Geography and Environmental Studies, along with Prof. Manfred Green, the head of the School of Public Health, and in collaboration with Prof. Jan Semenza from the ECDC. The Israeli research team was chosen by the EU's ECDC, after winning an international tender. The current study examined the link between daily temperature, humidity and precipitation data and West Nile incidence in Europe and neighboring countries. "We used statistical tools and found that as a result of heat waves, a dramatic increase in the number of cases resulted from increased activity of the virus and a growth of the mosquito population," claims Paz. According to her, these results were seen in various countries.

Paz says these results have a significant importance considering the rising temperatures seen in Europe in recent years. She is now conducting a continuing study on the subject for the ECDC and the French research center, CIRAD. "In our new research our aim is to look for additional potential influences on the spread of the disease, such as the location of mosquito populations or various human aspects," she says.

SOURCE: http://www.sciencedaily.com/releases/2013/05/130513115227.htm

How Plants May Help Offset Global Warming

Could plants help to slow the march of global warming?

It's possible, suggests a new study, which finds that as climates warm around the world, plants may respond by releasing more aerosol particles into the atmosphere.

The research, published online April 28 in the journal Nature Geoscience, finds that these natural aerosols can fuel cloud formation, which may help cool a warming climate. [The Reality of Climate Change: 10 Myths Busted]

Aerosols are fine particles of solid or liquid matter, suspended in air. Most of the aerosol particles in Earth's atmosphere come from human activities such as vehicle exhaust, according to the environmental blog The Carbon Brief. Volcanic eruptions also contribute some aerosols to the atmosphere.

But a small percentage of atmospheric aerosols come from living plants, according to a news release from the International Institute for Applied Systems Analysis (IIASA), which co-sponsored the study.

Plants release gases such as water vapor and oxygen; these combine with the aerosols released from plants to form larger airborne particles that reflect sunlight and form cloud droplets.

"Everyone knows the scent of the forest," Ari Asmi, University of Helsinki researcher and co-author of the study, said in a statement. "That scent is made up of these gases."

To measure the cooling effect, researchers collected data from 11 sites around the world, measuring aerosol particle concentrations, plant gases and temperatures.

In warmer temperatures, it was revealed, plants emit more of the gases that stick to aerosol particles. These can lead to cloud formation and, as a result of cloud cover, cooler temperatures.

Other natural phenomenon may help to cool the planet: Some researchers believe that phytoplankton— microscopic plants that drift on ocean currents — may reduce carbon dioxide levels in the atmosphere and lower the atmosphere's temperature.

Other research finds that tropical rainforests, which also absorb massive amounts of carbon dioxide and release water vapor that forms clouds, are critical to stabilizing atmospheric temperatures.

It's unclear how much cooling might actually occur as a result of so-called "biogenic" aerosols.

"This does not save us from climate warming," Pauli Paasonen, lead author of the study, said in the release.

Though in some areas, such as the forests of Finland and Canada, the cooling effect can be as large as 30 percent, the overall global effect is very small, offsetting only about 1 percent of global warming, according to the study.

Nonetheless, the impact of plant-based aerosol formation is an important element in fine-tuning climate forecast models, the researchers believe.

"Aerosol effects on climate are one of the main uncertainties in climate models," Paasonen said in the release. "Understanding this mechanism could help us reduce those uncertainties and make the models better.

SOURCE:http://news.yahoo.com/plants-may-help-offset-global-warming-142248510.html