HEALTHISSUES

Noninfectious Illnesses Are Expected to Become Top Killers

2008-06-05T17:37:00.000-07:00

Tuesday 03 June 2008
by: Donald G. McNeil Jr., The New York Times

As the world's population ages, gets richer, smokes more, eats more and drives more, noncommunicable diseases will become bigger killers than infectious ones over the next 20 years, the World Health Organization is reporting.

(Photo: The New York Times)

The report, World Health Statistics 2008, shows that diseases like diarrhea, AIDS, tuberculosis, neonatal tetanus and malaria will become less important causes of death as heart disease, cancer, stroke, diabetes and traffic accidents claim greater percentages of victims. There will still be wide disparities, the report says. Infectious diseases will remain major killers in Africa but should decrease in Asia.

Dr. Ties Boerma, director of health statistics for the agency, said he had seen more obese people and more smokers in capitals around the developing world.

"We tend to associate developing countries with infectious diseases," he said, but heart disease and stroke are becoming "the chief causes of death in more and more countries."

Annual deaths from AIDS are expected to fall to 1.8 percent of all deaths in 2030 from more than 3 percent now, the report said.

Tobacco companies are aggressively marketing to young people in poor countries. Almost a quarter of smokers started before age 10, the W.H.O. said, and one of its surveys of teenagers found that 20 percent owned clothing with cigarette brand logos. Citing freedom of choice, the companies work to break down traditions preventing women from smoking.

Worldwide, 100 million people each year are impoverished by paying for health care, the report said. And 40 percent of pregnant women and infants do not get basic health care or immunizations.

Skin Cancer, Malaria, and the Hanta Virus are serious health risks of global warming

2008-06-05T17:29:00.000-07:00

Malaria
Malaria is a disease that will increase during global warming. It is one of the earliest recorded human diseases, and is spread by the bite of a female mosquito. Mosquitoes breed in warm, wet places. With the increase of rain and warmth during global warming, the population of mosquitoes will increase, making the risk of getting this disease also increase. Malaria means "bad air" in Italian referring to the time when people thought that it was caused by gases around areas where mosquitoes thrive.

When you are bitten by a infected mosquito, it sends parasites into your bloodstream. These parasites keep reproducing, making the disease more devastating. Symptoms are fever and chills that come and go, headache, weakness, and an enlarged spleen. An enlarged spleen could rupture, or require surgery to remove. People can live without a spleen, but not having one increases the risk of infections or other problems.

Hanta Virus
The Hanta Virus is a deadly respiratory disease carried by wild rodents. With Global Warming, the population of rodents will soar because there will be long periods of drought followed by warm, early spring, and rodents thrive in these climate conditions.

If you come in contact with a rodent or if you breathe air that contains their waste you could get the virus. Dogs and cats are not known to carry the Hanta Virus. People most likely to get it are people who work in fields, or install and fix things in basements or attics where rodents can nest.

Some symptoms may be flu-like symptoms with fever and chills, you may have a dry cough, nausea, vomiting, or diarrhea. You could experience fatigue and have a hard time breathing because your lungs could fill with fluid. If you have these symptoms please see a doctor right away.

Although there is some cure in Asia for their type of virus, in the United States ours is more devastating and we have treatments that enable survival; but only if you seek treatment immediately.

For more information go to these resources: Montana State University, the Centers for Disease Control and Prevention.

Skin Cancer
Skin cancer is one of the main cancer concerns of the world when Global Warming hits. The skin cancer people get most is melanoma. Though melanoma is the most common, it is also the most curable and and can even be prevented. Early discovery is very important. If you have moles that are bothering you or are doing weird things such as changing size, shape, color, or if they bleed constantly, you should consult a doctor.
Suntan CartoonTo prevent skin cancer you should wear sunscreen and stay in the shade. You should also wear light color clothing and a hat so your head and body can stay safe. You should steer clear of tanning salons, their tanning beds have the same ultraviolet rays as the sun. Remember, stay safe so you can fun in the sun. For more information checkout the American Medical Association or the Centers for Disease Control and Prevention.

Note: What we have written here is not intended to take the place of your doctor's advice. Please talk to your family doctor if you have any questions.

Adapted from http://library.thinkquest.org/J003411/health.htm

Report: Polluted Air Puts Millions at Risk

2008-06-02T02:55:00.000-07:00

from WebMD — a health information Web site for patients

Todd Zwillich

May 2, 2008 — Up to 125 million Americans are breathing air that puts their health at risk, a report released Thursday by the American Lung Association estimates.

The report shows that dozens of U.S. cities and counties regularly have unsafe levels of particulate and ozone smog pollution. Such pollution is a risk factor for worsening illness in people with asthma and other diseases but could also pose risks to healthy people, the report states.

The annual report ranks U.S. cities and counties on the number of unsafe air days throughout the year.

"Los Angeles remains the most ozone-polluted city in the nation," American Lung Association Vice President Janice Nolan told reporters. The city also scored at the top of the list for worst year-round particulate exposure.

Pollution's Effects

Ozone pollution is produced when exhaust from cars, power plants, and other sources reacts chemically in sunlight. Particle pollution is a mix of solid particle and liquid droplets in the air. It can include soot, dust, pollen, chemicals, and metals.

Both forms of pollution can worsen conditions such as bronchitis, asthma, emphysema, and cardiovascular disease.

"This process wreaks havoc in people with chronic lung disease," says Norman H. Edelman, MD, the American Lung Association's chief medical officer.

Overall ozone levels dropped about 7% nationwide between 1997 and 2006, according to Environmental Protection Agency (EPA) data. But the EPA angered environmental groups in March when it set a more lax ozone pollution standard than scientific advisors said was necessary to protect human health.

A report issued last week by the National Academy of Sciences (NAS) confirmed that ozone pollution poses risks to children, the elderly, and people with chronic diseases. But NAS experts also issued a statement declaring that "premature deaths are not limited to people who are already within a few days of dying."

After Los Angeles, cities with the worst year-round particle pollution included:

Pittsburgh
Bakersfield, Calif.
Birmingham, Ala.
Visalia-Porterville, Calif.
Atlanta
Cincinnati

After Los Angeles, cities with the worst ozone pollution included:

Bakersfield, Calif.
Visalia-Porterville, Calif.
Houston
Fresno, Calif.
Sacramento, Calif.
Dallas/Ft. Worth
New York/Newark, N.J.

American Lung Association President Bernadette Toomey says the group is lobbying Congress to order tougher ozone and particulate standards. "Americans are still being denied the health protection they deserve under the Clean Air Act," she says.

Efforts to force stricter standards could be part of a congressional debate on global warming expected this summer.

Business groups lobbied against stricter ozone and particulate standards, saying many companies and utilities aren't required to implement existing standards until 2013.

"Air quality around the United States continues to improve under the existing standards," says Bryan Brendle, an energy lobbyist for the National Association of Manufacturers, an industry group.

Ozone: Top 25 Cities

Here are the top 25 cities for ozone pollution:

1. Los Angeles-Long Beach-Riverside, CA

2. Bakersfield, CA

3. Visalia-Porterville, CA

4. Houston-Baytown-Huntsville, TX

5. Fresno-Madera, CA

6. Sacramento--Arden-Arcade--Yuba City, CA-NV

7. Dallas-Fort Worth, TX

8. New York-Newark-Bridgeport, NY-NJ-CT-PA

9. Washington-Baltimore-Northern Virginia, DC-MD-VA-WV

10. Baton Rouge-Pierre Part, LA

11. Philadelphia-Camden-Vineland, PA-NJ-DE-MD

12. Charlotte-Gastonia-Salisbury, NC-SC / San Diego-Carlsbad-San Marcos, CA / Atlanta-Sandy Springs-Gainesville, GA-AL

15. St. Louis-St. Charles-Farmington, MO-IL / Beaumont-Port Arthur, TX

17. Merced, CA

18. El Centro, CA

19. Phoenix-Mesa-Scottsdale, AZ

20. Kansas City-Overland Park-Kansas City, MO-KS

21. Modesto, CA

22. Birmingham-Hoover-Cullman, AL

23. Las Vegas-Paradise-Pahrump, NV

24. Chicago-Naperville-Michigan City, IL-IN-WI / Hanford-Corcoran, CA / Milwaukee-Racine-Waukesha, WI

Particle Pollution: Top 25 Cities

Here are the top 25 cities for particle pollution:

1. Los Angeles-Long Beach-Riverside, CA

2. Pittsburgh-New Castle, PA

3. Bakersfield, CA

4. Birmingham-Hoover-Cullman, AL

5.Visalia-Porterville, CA

6. Atlanta-Sandy Springs-Gainesville, GA-AL

7. Cincinnati-Middletown-Wilmington, OH-KY-IN

8. Fresno-Madera, CA / Hanford-Corcoran, CA / Detroit-Warren-Flint, MI /Cleveland-Akron-Elyria, OH

12. Macon-Warner Robins-Fort Valley, GA

13. St. Louis-St. Charles-Farmington, MO-IL

14. Weirton-Steubenville, WV-OH / Charleston, WV

16. Lancaster, PA / York-Hanover-Gettysburg, PA

18. Louisville-Jefferson County-Elizabethtown- Scottsburg, KY-IN

19. Rome, GA / Huntington-Ashland, WV-KY-OH

21. Augusta-Richmond County, GA-SC

22. Washington-Baltimore-Northern Virginia, DC-MD-VA-WV / Canton-Massillon, OH / Greenville-Spartanburg-Anderson, SC

25. Columbus-Auburn-Opelika, GA-AL / Hagerstown-Martinsburg, MD-WV

Cleanest Cities

Here are the cleanest cities for ozone pollution, in alphabetical order:

Albuquerque, NM
Ames-Boone, IA
Appleton-Oshkosh-Neenah, WI
Austin-Round Rock, TX
Bangor, ME
Bellingham, WA
Bloomington, IN
Bloomington-Normal, IL
Bowling Green, KY
Brunswick, GA
Burlington-South Burlington, VT
Cape Coral-Fort Myers, FL
Carson City, NV
Cedar Rapids, IA
Champaign-Urbana, IL
Davenport-Moline-Rock Island, IA-IL
Decatur, IL
Des Moines-Newton-Pella, IA
Duluth, MN-WI
Elmira, NY
Eugene-Springfield, OR
Fargo-Wahpeton, ND-MN
Florence-Muscle Shoals, AL
Gadsden, AL
Gainesville, FL
Hickory-Lenoir-Morganton, NC
Honolulu, HI
Lafayette-Frankfort, IN
Laredo, TX
Lexington-Fayette--Frankfort--Richmond, KY
Lincoln, NE
Logan, UT-ID
Medford, OR
Montgomery-Alexander City, AL
Naples-Marco Island, FL
Ocala, FL
Omaha-Council Bluffs-Fremont, NE-IA
Peoria-Canton, IL
Port St. Lucie-Sebastian-Vero Beach, FL
Rapid City, SD
Reno-Sparks-Fernley, NV
Roanoke, VA
Rochester, MN
Rochester-Batavia-Seneca Falls, NY
Rockford-Freeport-Rochelle, IL
Salinas, CA
Savannah-Hinesville-Fort Stewart, GA
Sioux Falls, SD
Spokane, WA
Springfield, IL
Utica-Rome, NY
Waterloo-Cedar Falls, IA
Wilmington, NC
Yuma, AZ

SOURCES: "State of the Air: 2008," American Lung Association, May 1, 2008; Janice Nolan, vice president, American Lung Association; Norman H. Edelman, MD, chief medical officer, American Lung Association; "Estimating Mortality Risk Reduction and Economic Benefits from Controlling Ozone Air Pollution," National Academy of Sciences, April 22, 2008.

Adapted from http://www.medscape.com/viewarticle/573910

Health Dangers from a Warming Planet

2008-06-01T05:18:00.000-07:00

Health and Global Warming

Katrina's aftermath: New Orleans residents are rescued from flood waters. Photo: Jocelyn Augustino/FEMA

Devastating Storms

Nearly half the U.S. population lives in coastal areas, making stronger hurricanes and storms a particular threat. One need only remember the tragic aftermath of Hurricane Katrina to know how much death and destruction one powerful storm can wreak. (Get details on hurricanes and climate change.)

Loss of life. Katrina, which pummeled the Gulf Coast and flooded New Orleans in 2005, was the sixth strongest hurricane ever recorded and the third strongest that made landfall in the U.S. It was also one of the deadliest, implicated in the death of nearly 2,000 people.
Carbon monoxide poisoning. Hurricanes can lead to carbon monoxide poisoning when people use portable generators in response to power outages. After Hurricane Charley struck Florida in 2004, at least 167 people died of carbon monoxide poisoning.
Illness from contaminated food and water. Waste- and debris-filled flood waters can pollute drinking water or food supplies, causing gastrointestinal disease or forcing people to go hungry. Children playing in contaminated floodwater can become sick or get bitten by insects or snakes. Cleanup workers or volunteers may also suffer health problems. (See how flooding can cause dangerous water pollution problems.)

Katrina's force unleashed debris, raw sewage and a slew of toxins into flood waters. Many first-responders and ordinary citizens in New Orleans reported nausea and vomiting. Some experienced rashes and blisters after contact with dirty flood waters; others suffered breathing problems from toxic fumes or mold spores. (See also Hurricane Katrina Water Contamination.)

Damage to public health infrastructure. Rescue efforts are hampered by power outages or damage to buildings that deliver care. Several major New Orleans hospitals experienced flooding and power outages during Katrina, leaving those needing life-support systems and other electrically powered equipment at the mercy of emergency generators; some patients did not survive.
Anxiety, depression and post-traumatic stress disorder. Even years after a disaster, many victims suffer psychological aftereffects. For example, over 38 percent of the people who came to an interim Emergency Department in New Orleans after Hurricane Katrina were later diagnosed with Post-Traumatic Stress Disorder (PTSD).

Deadly Heat Waves

Scientists predict that severe heat waves will become more common as global warming continues. In the past several decades, extreme heat has become more deadly than hurricanes, tornadoes, lightning, floods and earthquakes — combined. (Get details on heat waves and climate change.)

The dangers include:

Heat stroke or exhaustion. People suffer heat-related illness when their natural "thermostats" cannot cope with too much heat and their body temperature rises rapidly. Sweating normally cools us down, but with intense heat that may not be enough. Heat stroke is the most serious heat-related illness and can cause death or permanent disability if not treated promptly.

During Europe's 2003 heat wave, one of the most lethal ever, a staggering 70,000 people died as a result of the relentless heat, breaking all records for heat-induced fatalities.

Breathing problems. More hot days mean ripe conditions for ozone smog, which forms when pollutants from tailpipes and smokestacks mix with sunlight, heat and stagnant air (and thus occurs mostly during the summer months). Smog triggers asthma attacks and worsens other breathing problems. Hospital admissions and emergency room visits for respiratory illnesses rise during periods of high smog levels. (See Asthma and Air Pollution).

The blistering heat wave of 2006 is a sobering case in point. As the heat swept across the U.S., America’s skies were filled with unsafe levels of smog. (See fact sheet Global warming, heat waves and unhealthy air [PDF].)

The risks of heat-related health problems may be exacerbated by:

Increasing urbanization. About half the world's population live in urban areas (compared with about a third in 1970). Cities become "heat islands," with asphalt and buildings diminishing the cooling effect of vegetation and trees. By 2030, nearly two-thirds of the population is expected to live in urban areas. The combination of longer stretches of scorching days and increasing urbanization means ripe conditions for illness or death from heat.

In places with extreme temperature variations between winter and summer, like Chicago and New York, the risk of death from heat waves goes up. Cities in temperate climates tend to be less prepared to cope with excessive heat, while normally hot places like Miami and Houston are better equipped (for example, more buildings and homes have air conditioning). (See How Much Heat Can We Stand?)

Perilous blackouts. Heat waves up the ante for power outages. Long periods of hot weather push up electricity demand, straining the power grid and increasing the likelihood of blackouts. The elderly and infirm are particularly vulnerable. Without power to run air conditioners or elevators, people who have limited mobility or are in poor health may suffer or die in overheated apartments (see Who's at Risk?).

Raging Wildfires

Wildfires are on the rise in the U.S. As the climate warms, hot, dry summers are creating tinderbox conditions ideal for wildfires. Climate change is projected to increase wildfire risk across much of the West (see Wildfires on the Rise).

In fall 2007, wildfires in Southern California destroyed over 1,500 homes, burned 500,000 acres of land, and displaced more than 900,000 people. Besides damage to property and to forests, wildfires can also cause debilitating injuries:

Hazardous air quality. Fires produce smoke, noxious gases, and tiny soot particles. The smoke can be transported hundreds or even thousands of miles to urban centers, exposing millions of people to wildfire fumes and worsening air quality. Over the longer term, air pollution from wildfires exacerbates eye, heart, and lung diseases. Children, the elderly and people with chronic heart or lung problems are especially at risk. (See more about smoke from wildfires.)
Burns. A big risk for people in the midst of a wildfire is, of course, getting burned. Caring for burn victims and preventing infection are difficult tasks, and many burn victims remain disabled. In the 2007 California wildfires, the San Diego medical center cared for more than 50 burn victims.

Spread of disease

In some regions, a changing climate may also increase cases of tropical mosquito-borne diseases like malaria, waterborne diseases like gastrointestinal illness and even viruses carried by mice such as hantavirus. (See Diseases Spread as Climate Changes and Virus from Africa Spreading in a Warmer Italy.)

Mosquito-borne diseases. Malaria and other infectious diseases carried by mosquitoes are a problem mostly in tropical countries. Heavy rainfall and humidity help breed disease-carrying insects like mosquitoes. Studies indicate that higher winter temperatures expand the range where mosquitoes can survive, increasing the likelihood of disease outbreaks farther north or at higher altitudes.
Waterborne disease outbreaks. More than half of all waterborne diseases in the U. S. occur after major rainfall events. The most common is diarrhea from drinking contaminated water. Heavy rainfall can overflow sewer systems and wash waste and chemicals into rivers and oceans. Runoff can cause coliform bacteria outbreaks and algae blooms that prevent people from swimming or eating fish from those waters.

What you can do

This dire list does not have to play out in full force. You can help by:

support national action to cap global warming pollution, and
make small healthful changes in your daily life to help slow the effects of global warming.

Adapted from http://www.edf.org/page.cfm?tagID=20916
june1st 2008

Are You at Risk?

2008-06-01T05:14:00.000-07:00

Health and Global Warming

An evacuated family driven from their San Diego home by the 2007 wildfires. Photo: Michael Raphael/FEMA

Do you have children?

Because they are still developing physically, breathe faster than adults and rely on adults for care, children are more vulnerable. Watch out for:

Heat waves. Infants and children up to four years old are particularly sensitive to heat and also rely on a care-giver to keep them adequately hydrated.
Smog and soot pollution. Because their lungs are still developing, children can suffer irreversible lung damage as adults from breathing unhealthy air when young.
Food- and waterborne diseases. Small children and children living in poverty are at higher risk for falling ill from diseases that climate change will likely exacerbate.
Stress, anxiety, depression or post-traumatic stress disorder after disastrous extreme weather events.

Are you over 65 years old?

The U.S. population is aging; by 2030 one fifth is projected to be older than 65. Older adults often have frail health and limited mobility, making them more vulnerable to:

Heat waves. Older adults with limited incomes may not have air conditioning and may have difficulty getting to air conditioned centers, if available. That can be deadly. The elderly are less resilient to temperature extremes in general.
Floods and other natural disasters. Hurricane Katrina showed all too clearly how a disproportionate number of senior citizens often suffer or die during a disaster.

Do you have a chronic medical condition?

People with heart problems, respiratory illnesses, diabetes or compromised immune systems are more prone to exacerbated health problems from:

Extreme weather-related disasters. Disruption of ongoing medical care and medicines is dangerous for the chronically ill.
Heat waves. People with diabetes are at greater risk of death from heat waves.
Bad air quality. Stagnant hot air masses and higher ozone and soot concentrations worsen heart and lung conditions. People with diabetes are also more susceptible to harm from air pollution.
Transmitted disease and illness. People with weakened immune systems, such as those with AIDS or those taking certain drugs to treat cancer, have less ability to fight off diarrhea from waterborne microbes or fevers from spreading viruses or mosquito-borne illnesses.

Are you pregnant?

Pregnant women and their unborn children are particularly susceptible to:

Food-borne illnesses and other climate-sensitive diseases. Certain medications to treat infections may not be recommended for pregnant women.
Ill effects from extreme weather disasters. Disruption of health care access, exposure to toxins, unsafe conditions, and psychological stress following disasters can endanger pregnant women and the health of the fetus.

Is your family income on the low end?

An income of $21,200 for four people living in the contiguous 48 states (or $26,500 if you live in Alaska and $24,380 in Hawaii) is considered below the poverty level. Lower-income populations are disproportionately affected by:

Heat waves. Concentrations of lower-income populations in inner-city neighborhoods often mean a disproportionate number suffer from the heat island effect: tall building and concrete intensify scorching days and stifling nights. People living in dwellings lacking air conditioning or windows that open face a higher risk of death.
Extreme weather disasters. People with lower incomes may not have the means to evacuate quickly out of harm's way. Access to medical care is more easily disrupted for lower income individuals. Katrina showed us the devastation that a natural disaster can bring to people living in poverty.

Do you live in an area with unhealthy air quality?

More hot days likely mean more smoggy unhealthy-air days. That's because sunlight and heat spark a chemical reaction between ground-level ozone and other pollutants to form smog. If you live in an area already plagued by smog and soot, be prepared. Exposure to unhealthy air is not good for anybody but is particularly bad if you:

Exercise outdoors regularly. On red-alert days, even the healthiest people should not exercise outdoors. Breathing in ozone singes your lungs much like a sunburn and repeated exposure can reduce lung function.
Work outside. More exposure to polluted air puts you at greater risk of health problems. Working outside in a rural or suburban area is an added risk factor for getting infectious diseases carried by insects and ticks, like Lyme disease, that may proliferate in a warmer climate.

Do you live in a region that is especially prone to harmful climate change?

Some regions of the U.S. may be more affected by particular dangers than others. What can you expect if you live in the following regions?

Southeast Atlantic and Gulf Coast. Residents of low-lying coastal areas will likely experience the one-two-three punch of more violent storms, strong storm surges and flooding, and coastal erosion. That will mean more damage to buildings and roads and possible contamination of drinking water.
Southwest: Higher temperatures and less rainfall in an already hot, arid climate will likely strain already taxed water resources. The chances for wildfires and dangerously bad air quality will go up.
Northwest: Heavy rainfall may lead to flooding and sewage overflow, causing illness and spread of disease.
The Great Plains: Milder winters and scorching summers could take a toll on the country's" bread basket" and hinder food production. Residents of cities would particularly suffer from intense heat waves.
Northeast: Rising temperatures could mean more allergies, the spread of diseases carried by insects or animals, such as hantavirus, and the expansion of West Nile virus and Lyme disease northward into Canada.
Alaska: Melting permafrost and retreating sea ice are already disrupting residents' lives and subsistence hunting and fishing. Milder temperatures are allowing more pests such as spruce bark beetles to proliferate.

Is your city or state prepared for climate change?

Warning systems and disaster preparedness save lives. See how your city or state measures up:

Cities with a Heat Health Watch/Warning System:

Dallas/Fort Worth;
Cincinnati/Dayton;
Chicago;
Jackson, Miss.;
Lake Charles, La.;
Little Rock, Ark.;
Memphis, Tenn.;
New Orleans;
Philadelphia;
Phoenix;
Portland;
St. Louis;
Shreveport, La.,
Seattle; and
Yuma, Ariz.

Philadelphia’s heat-watch warning system has already saved lives and shown that these systems can be effective and low-cost.

Thirty-three states have climate action plans or are creating them. For a detailed list, see the Pew report "Adaptation Planning" [PDF].

Six states have adaptation plans in progress:

Alaska (mostly addresses relocation)
California (includes public health): Climate Change Center and detailed report [PDF]
Florida
Maryland
Oregon
Washington

Six more recommend developing plans:

Arizona,
Colorado,
New Hampshire,
North Carolina,
Utah and
Vermont.

How you can help

Share Tips for a Healthy, Low-Carbon Life with friends and family.
Tell Congress to cap America's global warming pollution.
Find other ways to help slow global warming.

Adapted from http://www.edf.org/page.cfm?tagID=20900
june 1st 2008

Global Warming Impacts: Health Effects

2008-05-29T20:20:00.000-07:00

Doctors and scientists around the world are becoming increasingly alarmed over global warming’s impact on human health. Abnormal and extreme weather, which scientists have long predicted would be an early effect of global warming, have claimed hundreds of lives across the US in recent years. Our warming climate is also creating the ideal conditions for the spread of infectious disease, putting millions of people at risk.

As part of its research the Intergovernmental Panel on Climate Change (IPCC), a United Nations sponsored organization made up of over 2500 of the world’s leading scientists, examined the impacts global warming will likely have on human health. They concluded that human induced climate change "is likely to have wide-ranging and mostly adverse impacts on human health, with significant loss of life."

The IPCC's results are a grim indication that in the future rising temperatures may be measured in bodies, not degrees.

Global Warming Impacts: Infectious Disease

Malaria. Dengue Fever. Encephalitis. These names are not usually heard in emergency rooms and doctor’s offices in the United States. But if we don’t act to curb global warming, they will be. As temperatures rise, disease-carrying mosquitoes and rodents spread, infecting people in their wake. Doctors at the Harvard Medical School have linked recent U.S. outbreaks of dengue ("breakbone") fever, malaria, hantavirus and other diseases to climate change.

Dengue Fever

Dengue, or "breakbone", fever is a mosquito borne disease related to yellow fever. Unlike its relative, however, there is no vaccine against dengue. One strain of the disease, hemorrhagic dengue fever, is often deadly, and doctors in the U.S. and other areas into which it is expected to spread have little experience diagnosing or treating it.

The range of the mosquito which carries dengue fever is limited by temperatures. Frost kills both adults and larvae. In the past, this has prevented the disease from spreading from the tropics, but rising temperatures are changing that. It has moved steadily north in recent decades, and to higher elevations. In the United States the mosquito which carries dengue has reached as far north as Chicago.

Dengue fever has already infected victims in the US. When McAllen, Texas suffered an outbreak of the disease in 1995, the Houston Chronicle's headline read, "Warming Climate Invites Dengue Fever to Texas."

Malaria

Like dengue fever, malaria is a mosquito borne illness normally limited by temperatures. Rising temperatures have expanded its range, and exposed new populations to infection. IPCC scientists project that as warmer temperatures continue to spread north and south from the tropics and to higher elevations, malaria-carrying mosquitoes will spread with them. They project that global warming could put as much as 65 percent of the world’s population at risk of infection by malaria.

Here in the United States malaria infections are already on the rise. Houston has experienced a malaria outbreak in each of the last two years. In the last three years malaria cases have occurred as far north as New Jersey, Michigan and Queens, New York. In 1997 an outbreak occurred in Florida, striking the Disney World theme park, and mosquitoes carrying the illness were discovered in New York.

Cholera and Encephalitis

Climate-related increases in sea surface temperatures and sea level can lead to higher incidence of water-borne infectious and toxin-related illnesses such as cholera and shellfish poisoning; zooplankton which can harbor cholera proliferate in warmer water temperatures, and provide a potential environmental reservoir for the disease. Cholera killed 120,000 world-wide people in 1995, most of them children.

Outbreaks of encephalitis, another illness with strong links to warmer temperatures, also appear to be on the rise. Since 1987 there have been major outbreaks in Florida, Mississippi, New Orleans, Texas, Arizona, California, and Colorado.

Global Warming Impacts: Deadly Weather

The IPCC projects that more frequent and more severe heat waves will be one lethal effect of global warming. Deadly stretches of hot days, where nighttime temperatures remain high, will become more common. One such event killed over Chicago during the summer of 700 people in 1995. Based indicates on past heat wave events, research that by the year 2020, global warming could cause up to a 145% rise in mortality in New York City. Other major cities could suffer similar problems.

Regional climate stress on agriculture may mean up to 300 million additional victims of malnutrition world-wide each year. Extreme floods and droughts are projected to become more severe as global warming worsens. These extremes may threaten the availability and supply of safe drinking water. Diseases associated with flooding, such as cryptosporidiosis, could affect millions more people every year.

Extreme weather events, like the abnormal storms and flooding that have devastated many communities across America in recent years, may also become more common. As the number and severity of these events increase they will pose not only an immediate threat to human health and well being, but also bring dangerous long-term consequences.

Heatwave deaths in Midwestern cities may soar due to global warming

CITY	CURRENT DEATHS IN PRESENT CLIMATE	2020 *CLIMATE AVERAGE DEATHS	2050 *CLIMATE AVERAGE DEATHS
Buffalo, NY	33	34.3	55.3
Chicago,IL	191	400.7	497.3
Cleveland,OH	29	39	52.3
Detroit,MI	110	162.7	219
Indianapolis,IN	36	55.7	70
Kansas City, MO	49	115	127.3
Minneapolis,MN	59	129.3	174.7
Pittsburgh,PA	39	54	79.7
St. Louis,MO	79	160	185.3

Numbers derived from averages from three models -- United Kingdom Meteorological Model, Global Fluid Dynamics Laboratory Model, and Max Planck Institute for Meteorology Model. Population and metropolitan areas standardized to current levels. Lives spared due to warmer winters estimated to be negligible. Adapted from Laurence S. Kalkstein and J. Scott Greene.

Global Warming Impacts: Health Effects - Conclusions

The world's leading authority on global warming, the Intergovernmental Panel on Climate Change (IPCC), has concluded that unchecked global warming will cause a significant increase in human mortality due to extreme weather and infectious disease. No country, even industrialized nations like the United States, will escape these impacts.

Here in the US global warming may already be harming public health. Houston has experienced a malaria outbreak in each of the last two years. In the 1990s malaria cases have occurred as far north as New Jersey, Michigan and Queens, New York. Malaria could become even more common in the US as global warming worsens. IPCC scientists project that as warmer temperatures spread north and south from the tropics, and to higher elevations, malaria-carrying mosquitoes will spread with them. They conclude that global warming will likely put as much as 65% of the world's population at risk of infection—an increase of 20%.

When McAllen, Texas suffered a severe outbreak of dengue fever in 1995, the Houston Chronicle's head-line read,"Warming Climate Invites Dengue Fever to Texas." Epidemiologists reported that an unusually mild winter and hotter than normal summer contributed to the spread of the disease, which is carried by mosquitoes.

Outbreaks of encephalitis, another mosquito-borne illness with strong links to warmer temperatures, are also on the rise. Since 1987 there have been major outbreaks in Florida, Mississippi, New Orleans, Texas, Arizona, California, and Colorado.

Global warming will have numerous damaging impacts on human health. Spreading infectious disease, longer and hotter heat waves, and extreme weather will all claim thousands of additional lives nationwide each year. If global warming continues unabated, both we and our children will pay a terrible price.

We simply cannot afford to ignore the global warming problem.

Adapted from http://www.sierraclub.org/globalwarming/health/conclusions.asp

Experts: Global Warming Affects Health

2008-05-29T20:03:00.000-07:00

Health Officials Tell Senate Committee of Health Risks From Climate Change

By Todd Zwillich
WebMD Medical News

Reviewed By Louise Chang, MD

Oct. 23, 2007 -- Poor air quality, scarce water, even a more hospitable environment for disease-carrying mosquitoes. All of these are potential impacts of global warming on human health, federal and state health officials told a Senate panel Tuesday.

Public health officials warn that environmental changes are almost guaranteed to have an impact on people's health. The problem is, there are far more "unknowns" than "knowns," they said.

"I don't think in some of these areas it's a question of 'if.' It's a question of who, what, where, when, how -- and how bad it will be," CDC Director Julie Gerberding, MD, told the Senate Environment and Public Works Committee.

"What you're telling us is we'd better get ready for this and we'd better get ready for this now," said Sen. Barbara Boxer, D-Calif., who chairs the environment committee.

CDC officials warn that potential effects of global warming range from an increase in catastrophic weather events like hurricanes and heat waves, to lower water and food quality.

Boxer highlighted the case of a 14-year-old boy who died in September from a disease-causing amoeba after swimming in an Arizona lake. Following the death, CDC officials issued a warning for swimmers to avoid excessively warm or stagnant water, where the amoeba thrives.

"Right now it is a rare disease, but it is exactly the kind of thing we're here to talk about," Gerberding said.

Lungs and Air Quality

Other potential health problems are far less rare. Michael McCally, MD, executive director of Physicians for Social Responsibility, warned that much of the country already lives at increased risk of asthma and other respiratory problems due to ozone-related air pollution.

"Global warming undermines efforts to improve air quality as rising temperatures accelerate ozone formation in the summer months," he said.

Tennessee health commissioner Susan R. Cooper told lawmakers that heat waves and forest fires are beginning to stretch health departments nationwide.

"Our systems are being taxed by these events as they are appearing with increased frequency and greater severity," said Cooper, who represents the Association of State and Territorial Health Officials.

A Question of Resources

Still, global warming remains stubbornly unpredictable. While most researchers agree that human activity is warming the planet, no one knows exactly by how much. It's even harder to predict how humans will adapt, or fail to adapt, to changing conditions.

Several of the panel's Republicans warned that fear of global warming could divert precious resources away from effective health programs.

Sen. Kit Bond, R-Mo., said that aggressive efforts to curb carbon emissions leading to global warming will drive up energy costs for low-income Americans, which could lead to less money for heath care costs.

"What are the long-term effects of going without heart medication, blood pressure medication, or pain medication?" Bond said.

SOURCES: Julie Gerberding, MD, director, CDC. Sen. Barbara Boxer, D-Calif. Michael McCally, MD, executive director, Physicians for Social Responsibility. Sen. Tom Barasso, R-Wyo. Susan Cooper, commissioner, Tennessee Department of Health. Sen. Kit Bond, R-M

Human warming hobbles ancient climate cycle

2008-05-22T20:06:00.000-07:00

Human warming hobbles ancient climate cycle An ox is seen on dried-up rice fields in Baan Ban village in Ayuthaya province, about 59 miles north of Bangkok April 1, 2008. REUTERS/Sukree Sukplang

By Deborah Zabarenko, Environment Correspondent

WASHINGTON (Reuters) - Before humans began burning fossil fuels, there was an eons-long balance between carbon dioxide emissions and Earth's ability to absorb them, but now the planet can't keep up, scientists said on Sunday.

The finding, reported in the journal Nature Geoscience, relies on ancient Antarctic ice bubbles that contain air samples going back 610,000 years.

Climate scientists for the last 25 years or so have suggested that some kind of natural mechanism regulates our planet's temperature and the level of carbon dioxide in the atmosphere. Those skeptical about human influence on global warming point to this as the cause for recent climate change.

This research is likely the first observable evidence for this natural mechanism.

This mechanism, known as "feedback," has been thrown out of whack by a steep rise in carbon dioxide emissions from the burning of coal and petroleum for the last 200 years or so, said Richard Zeebe, a co-author of the report.

"These feedbacks operate so slowly that they will not help us in terms of climate change ... that we're going to see in the next several hundred years," Zeebe said by telephone from the University of Hawaii. "Right now we have put the system entirely out of equilibrium."

In the ancient past, excess carbon dioxide came mostly from volcanoes, which spewed very little of the chemical compared to what humans activities do now, but it still had to be addressed.

This antique excess carbon dioxide -- a powerful greenhouse gas -- was removed from the atmosphere through the weathering of mountains, which take in the chemical. In the end, it was washed downhill into oceans and buried in deep sea sediments, Zeebe said.

14,000 TIMES FASTER THAN NATURE

Zeebe analyzed carbon dioxide that had been captured in Antarctic ice, and by figuring out how much carbon dioxide was in the atmosphere at various points in time, he and his co-author determined that it waxed and waned along with the world's temperature.

"When the carbon dioxide was low, the temperature was low, and we had an ice age," he said. And while Earth's temperature fell during ice ages and rose during so-called interglacial periods between them, the planet's mean temperature has been going slowly down for about 600,000 years.

The average change in the amount of atmospheric carbon dioxide over the last 600,000 years has been just 22 parts per million by volume, Zeebe said, which means that 22 molecules of carbon dioxide were added to, or removed from, every million molecules of air.

Since the Industrial Revolution began in the 18th century, ushering in the widespread human use of fossil fuels, the amount of carbon dioxide in the atmosphere has risen by 100 parts per million.

That means human activities are putting carbon dioxide into the atmosphere about 14,000 times as fast as natural processes do, Zeebe said.

And it appears to be speeding up: the U.S. government reported last week that in 2007 alone, atmospheric carbon dioxide increased by 2.4 parts per million.

The natural mechanism will eventually absorb the excess carbon dioxide, Zeebe said, but not for hundreds of thousands of years.

"This is a time period that we can hardly imagine," he said. "They are way too slow to help us to restore the balance that we have now basically distorted in a very short period of time."

(Editing by Eric Walsh)

More Trees, Less Global Warming, Right? -- Not Exactly

2008-05-22T19:50:00.000-07:00

A 150-year simulation of worldwide deforestation finds that tropical forests are carbon sinks and boreal forests contribute to warming

By Nikhil Swaminathan

Before compact fluorescent light bulbs and ethanol, the first line of defense against global warming was planting trees.

Forests, after all, cool the atmosphere by drinking in carbon dioxide from the air. A new study, however, published in Proceedings of the National Academy of Sciences reports that forests' other climatic effects can cancel out their carbon cleaning advantage in some parts of the world. Using a three-dimensional climate model, the research team mimicked full global deforestation and also studied the effects of clear-cutting in different regions of latitude, such as the tropics and boreal zones. Apparently, these natural carbon sinks only do their job effectively in tropical regions; in other areas, they have either no impact or actually contribute to warming the planet. In fact, according to this model, by the year 2100, if all the forests were cut and left to rot, the annual global mean temperature would decrease by more than 0.5 degree Fahrenheit.

"I'm not sure the slight amount of cooling is necessarily significant, but that removing all the forest produced little change" on temperature is, says study co-author Ken Caldeira, an ecologist at the Carnegie Institution of Washington's Department of Global Ecology in Stanford, Calif. "I think what's interesting is this global cancellation was a product of very different responses at different latitudes."

Trees perform three major climate functions: They absorb carbon, which they pull from the atmosphere, creating a cooling effect; their dark green leaves absorb light from the sun, heating Earth's surface; and they draw water from the soil, which evaporates into the atmosphere, creating low clouds that reflect the sun's hot rays (a mechanism known as evotranspiration that also leads to cooling). These three factors—the second two being largely ignored in climate models up to this point, according to Caldeira—taken together created very different results in the primary latitudes studied: the equatorial tropic zone; the midlatitudes that include most of the U.S.; and the boreal areas, which are subarctic and include much of Canada, Russia and the northern extremities of the U.S.

In all three regions, forests dutifully perform their task of sucking carbon dioxide from the air, but light absorption and evotranspiration vary wildly. In tropical zones, forests have a significant, overall cooling effect. The soil is very wet and, so, via evotranspiration, the trees are covered by low-lying clouds that create a small albedo (power of light that is reflected by a surface). In nontropical areas, Caldeira explains, "the real significant factor is whether there's snow on the ground in the winter." If a forest covers a snowy expanse, "that has a strong warming influence," he notes, because of little cloud cover resulting from less efficiency in evaporating water. The poor cloud formation coupled with the intense absorption of light by the trees "far overwhelms the cooling influence of the carbon storage," he says.

"In midlatitudes, we got that it was basically a wash—the carbon dioxide effects were pretty much directly balanced by the physical effects," Caldeira says. He attributes this to the low contrast between light absorption from trees and from grass in pastures, though he notes that because there are some areas with wintry snow cover, the loss of a forest will probably have a slight, if any, cooling effect. He uses this example to point out the relative influence of the different forest functions. Whereas carbon levels can affect warming on a global scale, the effects of increased albedo and poor evotranspiration would affect temperatures only on a regional level. For instance, he says, "if you remove all the forest in the U.S., it would probably heat up the world, but have a slight cooling influence on the U.S., itself."

Navin Ramankutty, an assistant professor of geography and Earth system sciences at McGill University in Montreal, says this study is the first to take a comprehensive look at the consequences of deforestation on the entire world. "You can't just blindly go ahead and reforest and that will tackle climate change," he says, pointing out a key finding in the study. "If you think about conservation groups, they're all talking about planting trees. We should be protecting tress for other reasons."

Caldeira agrees, saying that protecting the forest should be part of an effort to sustain the world's biodiversity. He also adds that the findings do not endorse clear-cutting or destroying wildlife habitats. "I think that it's important to look at preventing climate change as a means rather than an end in itself," he says. "Too narrow a focus on global warming and a loss of the broader focus of protecting life on this planet can lead to perverse outcomes." Rather than looking to forests to solve the current climate crisis by capturing carbon dioxide, he suggests targeting our "energy system," which continues to create the pollutant.

GLOBAL WARMING ?

2008-05-22T19:13:00.000-07:00

By Mark Jaffe
Denver Post Staff Writer

Article Last Updated: 12/26/2006 12:27:55 PM MST

The words "global warming" provoke a sharp retort from Colorado State University meteorology professor emeritus William Gray: "It's a big scam."

And the name of climate researcher Kevin Trenberth elicits a sputtered "opportunist."

At the National Center for Atmospheric Research, where Trenberth works, Gray's name prompts dismay. "Bill Gray is completely unreasonable," Trenberth says. "He has a mind block on this."

Only 55 miles separate NCAR's headquarters, nestled in the Front Range foothills, from CSU in Fort Collins. But when it comes to climate change, the gap is as big as any in the scientific community.

At Boulder-based NCAR, researchers project a world with warmer temperatures, fiercer storms and higher seas.

From CSU, Gray and Roger Pielke Sr., another climate professor emeritus, question the data used to make those projections and their application to regional climate change.

Science by its nature is disputatious - with every idea challenged, tested and retested. It's always been that way.

In the 18th century, Sir Isaac Newton and Gottfried Leibniz sparred over claims to the discovery of calculus.

About 140 years later, Charles Darwin's theory of evolution was challenged - based on the science of the day - by Harvard University professor Louis Agassiz and the British Museum's Sir Richard Owen.

Now the battle is over global warming, or more accurately over myriad details - like temperature readings and the thickness of sea ice - upon which the larger idea is based.

On one hand, the fight is a natural part of the scientific process. But it also creates dissonance and uncertainty.

"Some of this noise won't stop until some of these scientists are dead," said James Hansen, head of the Goddard Institute for Space Studies in New York City, and among the first to sound the alarm over climate change.

While science is comfortable with uncertainty, policymakers are not, and that is what has turned this scientific debate into front-page headlines.

"I think there is a debate about whether it's caused by mankind or whether it's caused naturally," President Bush said in a July interview.

To be sure, Gray and Pielke are in a scientific minority. Still, their challenges remain part of the fractious scientific process.

"Science needs skeptics," said NCAR researcher Warren Washington.

Still, a broad scientific consensus has emerged that human activity is contributing to climate change.

Findings by panels created by the National Academy of Science to resolve disputes - such as conflicting satellite and ground temperature records - have supported the trends in global climate change.

And things that the NCAR models predict - such as thinning sea ice and melting glaciers - are coming to pass, although scientists say more data are needed to verify those trends.

After more than two decades of research, scientists, even most skeptics, agree that:

Since 1750, the amount of carbon dioxide in the atmosphere, mainly from burning fossil fuels, has risen to about 380 parts per million from 286 parts per million.

It doesn't appear carbon dioxide levels have been that high in the past 650,000 years.

Carbon dioxide is continuing to build in the atmosphere by about 1.5 parts per million a year, and as a so-called greenhouse gas, it traps the sun's heat.

The Earth's average temperature has warmed about 1 degree Fahrenheit since 1880 and is now warmer than it has been in the past 400 years.

Average global temperatures are likely to rise - this is where the debate begins - somewhere between 2 and 10 degrees Fahrenheit by 2100.

The heat will cause global ocean levels to rise 3 to 39 inches this century.

In the film "An Inconvenient Truth," former Vice President Al Gore tends to fix on the upper end of the projections, while skeptics point out that the lower end may be as likely and less catastrophic.

But even small changes may have big effects. When the average temperature dropped by a little less than 1 degree Fahrenheit in about 1400, it ushered a period called the "Little Ice Age."

It was a time when advancing Swiss Alp glaciers crushed villages, England's Thames River froze and short growing seasons led to famines.

Most scientists also agree extreme weather events like Hurricane Katrina or Los Angeles' July record 119-degree Fahrenheit temperature cannot be directly attributed to global warming.

On this much there is some scientific consensus.

What the impact of rising temperatures or higher seas will be is more open to debate, according to skeptics such as Pielke, because most of the calculations are global averages.

"This tells you nothing about what's going to happen in any region," Pielke said.

While Pielke agrees carbon dioxide is forcing changes in the climate, he says, "It is not the only forcing."

Man-made changes to the land, in addition to about 30 other greenhouse gases - some man-made, some natural - may play an even a bigger role, he said.

"The public likes simple answers," Pielke said. "But there isn't any simple answer here."

Simplicity is hard to come by because Earth is a giant, complex heat-moving machine.

The sun's rays strike full force at Earth's middle and glance off the ends - making the equator hotter than the poles.

Ocean currents, winds, the jet stream and hurricanes are forces trying to balance out the Earth's heat.

Efforts to calculate what is going on in the oceans, the land and the atmosphere are an unparalleled exercise.

The task falls to mathematical models run by supercomputers like the one in NCAR's basement. These "general circulation models" attempt to keep track of a multitude of variables around the globe - such as ocean currents, air and sea temperatures, rainfall and the composition of the atmosphere.

"This is a unique exercise in science and a very difficult one," said Christopher Essex, a mathematician at the University of Western Ontario in Canada.

The models are trying to project a future world, Essex said, without a complete theoretical base on how climate works and the risk of small errors being amplified.

Another problem, Essex said, is in the inability to do controlled experiments - one of science's key tools.

"There's only one atmosphere, so you can't hold everything steady and change just one variable to see what happens," he said.

Essex offered his critique of the models at a Los Alamos National Laboratory climate conference in Santa Fe in July.

At the end of the presentation, CSU's Gray jumped up and demanded: "Should we base national policy on these models?"

"I'm not touching that," Essex replied.

And then Essex added: "At every stage of the history of science, there has been some element that was impossible, and we've found a way around it. I am sure we will here."

This did not assuage Bill Gray.

Gray is among the most strident critics, quick to use words like "fraud" or "gang" to describe the modelers.

Instead of model projections, Gray looks at the history and patterns of weather to find trends.

And befitting his 76 years, Gray has a long view. His first report on climate - on the return of the dust bowl - was in the early 1940s when he was in junior high school.

"We'd gone through a warming trend in the '40s, and everybody was saying we were going to win World War II but face terrible droughts," Gray said.

Soon after, temperatures went into a cooling trend and by 1975, Gray points out, there was talk of a coming ice age.

The Earth does have natural cycles of cooling and warming - during the past 740,000 years there have been eight cycles with four ice ages.

The cycles appear to be tied to slight variations in the tilt of the Earth toward the sun.

During the last ice age - which ended about 10,000 years ago - Earth was on average about 4 degrees Fahrenheit cooler, and what is now Manhattan was buried under ice.

At some point the Earth will wobble on its axis again, setting the stage for an ice age.

There are other phenomena affecting global temperatures over time, such as El Niño, a Pacific Ocean warm-water mass that appears in roughly five-year cycles and changes world weather patterns.

And there is the Atlantic thermohaline current, a conveyor belt moving heat north on the surface and then dropping it to the ocean floor and heading back to the equator - a 1,200-year trip.

Changes in the current lead to changes in temperature. Somehow the models have to account for these natural variations too.

Gray believes that the warmer temperatures in the Northern Hemisphere are linked to a natural slowing in the thermohaline current, not the carbon dioxide.

Some of the models also show the current is slowing and that, along with warming oceans, adds to hurricane risks.

This has sparked one of the biggest scientific disputes of the moment.

It is a debate in which NCAR's Trenberth and CSU's Gray are, of course, on opposite sides.

Hurricanes feed on warm water, and Trenberth says that warmer sea-surface temperatures and increased atmospheric water vapor - both of which have been measured - will contribute to more intense hurricanes.

Gray - and other hurricane specialists, including Chris Landsea, the science and operations officer at the National Hurricane Center in Miami - say that the link doesn't yet exist and that models overstate the case.

Trenberth concedes that the changes being measured are small, but he adds, "They are all going in one direction."

Gray argues that heat by itself isn't enough - that there are other variables: The air has to be cooler than the ocean, the winds have to be agreeable.

The dispute led Landsea, who is a former Gray student, to quit as a member of a working group of the United Nations' Intergovernmental Panel on Climate Change, or IPCC.

Trenberth, 61, is the lead author for that working group, whose report is due next year.

The IPCC was created to assess - through a set of working groups - scientific, technical and socioeconomic information on climate change. It does not, however, do research.

Landsea, in an open letter to the science community, said the science working group was being "motivated by pre- conceived agendas" and was "scientifically unsound."

Even with that, Landsea says: "I am concerned about the trend in global warming. It is a problem."

The IPCC science working group - with more than 100 members - has been trying to forge a consensus on the best science, Trenberth said.

"But it is a struggle to accommodate every viewpoint," he said. "I don't know why Chris Landsea acted that way."

Landsea isn't the panel's only critic.

"The IPCC has become an inbred process," Pielke said. "All the scientists I know are doing legitimate work and believe in what they are doing. ... Still, it's a narrow view."

Pielke, 59, says his doubts about the climate record began during his stint as Colorado's climatologist when he realized how inaccurate the state's thermometer network was.

Placing a thermometer close to a building or near an air- condition vent can compromise readings, Pielke said.

When the winds blow from Denver, a Front Range thermometer is influenced by urban effects, Pielke said, and by agricultural activities when it blows from the north.

Multiply that by tens of thousands of thermometers around the world and the temperature record is suspect, he contends.

The modeling groups say that what is important is the warming trend.

NCAR's Washington, 70, a pioneer in climate modeling, said that 30 years ago the climate models kept track of just the atmosphere and oceans. Today they include more than 10 measurements, including sea ice, clouds and forest growth.

This year NCAR even added human land-use impacts on climate to the modeling.

Pielke, who argues that when it comes to climate change both science and policy have focused too much on the carbon dioxide buildup and ways to contain it, said he felt "vindicated."

NCAR researcher Linda Mearns, however, said the land- use impact "doesn't obliterate or remove the greenhouse gas problem."

"Roger tries to present it as though he's the lone voice," Mearns said. "That's not true."

The models still have problems, Trenberth and the other modelers concede - particularly assessing regional impacts.

When the NCAR model tries to show Denver's weather patterns, for example, summer thunderstorms keep coming about noon.

"We all know they come in the late afternoon, so that's a problem in the model," said Trenberth, who was born in New Zealand and trained at the Massachusetts Institute of Technology in Cambridge, Mass.

Many issues still have to be resolved, said Chris Folland, a researcher at Britain's Hadley Centre for Climate Prediction, but the science continues to point in one direction.

"We've shown that the climate change is a true thing," he said. "We've done that with global averages, since that was easiest.

"The American government might not agree," Folland said. "Most American scientists do."