If you can't take the heat, maybe you should get out of the city

(Photo of time and temperature during heat wave of 2005 from Flickr and swanksalot/Seth Anderson)

Cities retain heat more than rural or even suburban areas. A combination of steel, concrete and asphalt that absorb the heat and large buildings that break up cool breezes cause what's known as "urban heat islands." That heat is retained at night, with so little vegetation or soil moisture to cool it down.

In New York City, night-time temperatures are as much as 14 degrees higher than those in outlying areas as close as 60 miles away, according to a 2009 American Meteorological Society study.

Now researchers at the Met Office in London are saying there will be an increased effect of urban warming as CO2 concentrations in the air rise.

In case you haven't noticed, a heat wave has descended over Washington, New York and much of the East Coast, with temperatures up around 100 degrees. Too bad the Congressmen who mocked global warming during the cold, snowy winter, are out of town right now. They might begin to have second thoughts. (Though, probably not.)

Increased CO2 will only make things worse, Met scientists say. Urban areas are warming faster than rural ones, according to the Met study, published in Geophysical Research Letters. The researchers forecast daytime urban temperatures will increase 5 degrees Fahrenheit when CO2 levels reach 645ppm, probably by 2050. Night temperatures will rise by the same amount, their models say.

Climate change and rapidly increasing migration to cities, especially in third-world countries, will create health hazards, the study said.

Some climate change deniers have said death from cold equals or surpasses death from heat, so health should not be a concern. However, the U.S. Global Change Research Program said winter cold snaps increase death rates by 1.6%, while heat waves drive them up by 5.7%. So heat is more deadly than cold. And the number of hot nights in most cities is expected to increase significantly.

The heat wave in Chicago in 1995, which killed some 700 people, was deadly because temperatures didn't cool at night and apartments without air conditioning got hotter and hotter as the days went on and it didn't cool down at night.

The Intergovernmental Panel on Climate Change reports in 2007 predicted with increasing global warming, there would be more heat waves with hot nights as well as hot days.

"Every degree is huge, in a city," said Stuart Gaffin, co-author of the Meteorological Society's New York study. "It's the difference between a blackout and getting through a heat wave. NYC this week was flirting with a blackout because of increased demand for air conditioning. A blackout would compound the danger and drive up the number of fatalities in a hot spell.

Which tells us we need to increase the capacity and modernize the electrical grid. And also that we need a price on carbon to slow down emissions into the air that will make all this worse and worse.

(Source: ClimateWire)

Worldwide emissions of CO2 up 3% in past year

(Photo of a Montana power plant from Flickr and photographer ambimb)

News Update: Carbon dioxide emissions, a prime driver of global warming, grew 3% in 2007. The increase exceeded forecasts by international scientists in the Intergovernmental Panel on Climate Change report 2 years ago and suggested a trend that could result in the worst-case scenario for climate change put forth by IPPC, which predicted a temperature rise of 4 to 11 degrees F by 2100. While 3% doesn’t sound like a lot, consider what will happen if that rate of increase persists for 10 or 20 years. China led the growth last year, providing more than half the increase. The U.S. was second, with a 2% increase, after emissions declined the previous year. Several industrial countries cut their emissions in 2007. Since 1992, world emissions have grown 38%, though the Kyoto Protocol called for a cut of 5% below 1990 levels by 2012. “If we’re going to do something [about the rate of growth] it’s going to have to be different than what we’re doing,” said Gregg Marland, a senior Department of Energy scientist. (Sources: Greenwire, thedailygreen.com, AP)

Undisturbed forests store more carbon than logging plantations to help fight global warming

(Photo of old growth eucalyptus tree from Flickr and photographer Tony from Sidney)

News Update 1: A new Australian study says natural forests, with their taller trees and larger canopies, store 60% more carbon than plantation, or industrial, forests. They also store more than the Intergovernmental Panel on Climate Change estimated in its 2007 report. Researchers at Australian National University found that in addition to growing larger, untouched trees grew older and stored carbon longer than trees cut down on a rotating basis. Biomass and soil store about 3 times as much carbon as that in the atmosphere, the report said, and 35% of the CO2 in the atmosphere came from past deforestation, while 18% of annual carbon emissions now are from deforestation. (Source: Reuters)