REUTERS/Jim Young
Former U.S. presidential candidate Al Gore delivers a speech on America's future energy needs in Washington, July 17, 2008.

By Jasmin Melvin and Deborah Zabarenko
Reuters

WASHINGTON - Al Gore, the Nobel Prize-winning crusader on climate change, challenged the United States on Thursday to commit to producing all U.S. electricity from renewable sources like solar and wind power in 10 years.

"Our dangerous over-reliance on carbon-based fuels is at the core of all three of these challenges -- the economic, environmental and national security crises," the former Democratic vice president and presidential candidate in 2000 told a meeting in Washington.

"So today I challenge our nation to commit to producing 100 percent of our electricity from renewable energy and truly clean carbon-free sources within 10 years," he said.

Gore also took aim at the Bush administration's policies on climate change, without mentioning the president by name. Advocates of tougher measures to combat global warming caused by carbon emissions have long said President George W. Bush has done too little about climate change.

Gore, who faced a smattering of protesters rallying against big government outside the hall, likened the fight against climate change to the successful challenge in the 1960s to send humans to the Moon within the decade.

Gore, who starred in the Academy Award-winning documentary "An Inconvenient Truth" about the perils of global warming, also disparaged goals set too far in the future.

"A political promise to do something 40 years from now is universally ignored because everyone knows it's totally meaningless. Ten years is about the maximum time that we as a nation can hold a steady aim and hit our target."

Bush has opposed economy-wide limits on the emission of climate-warming carbon dioxide. Last week, he and other leaders of the Group of Eight major industrialized nations offered a non-binding pledge to cut emissions 50 percent by 2050 -- 42 years from now.

"WE MUST MOVE FIRST"

The Bush administration and the other rich nations said they could not meet this goal without participation from developing economies like China and India.

Gore, noting that an international climate change treaty is expected to be concluded by the end of the next U.S. president's first year in office, questioned any delay on combating global warming.

"It is a great error to say that the United States must wait for others to join us in this matter," he said. "In fact, we must move first, because that is the key to getting others to follow; and because moving first is in our own national interest."

Democratic presidential candidate Barack Obama said he supported Gore's challenge, and said he would fast-track investments in renewable energy like solar, wind and biofuels if elected. "It's a strategy that will create millions of new jobs that pay well and cannot be outsourced, and one that will leave our children a world that is cleaner and safer," he said.

Obama's rival in the November election, Republican candidate John McCain, also backed Gore's plan. "If the vice president says it's do-able, I believe it's do-able," he told reporters.

Gore said he had had conversations with Obama, McCain, and with Bob Barr, the Libertarian Party candidate.

By Deborah Zabarenko

Reuters Environment Correspondent

WASHINGTON - The U.S. Environmental Protection Agency, under fire for apparently discounting the impact of climate change, on Thursday said global warming poses real risk to human health and the American way of life.

Risks include more heat-related deaths, more heart and lung diseases due to increased ozone and health problems related to hurricanes, extreme precipitation and wildfires, the agency said in a new report.

"Climate change poses real risk to human health and the human systems that support our way of life in the United States," the agency's Joel Scheraga said in a telephone briefing.

The report does not specify how many people in the United States could die due to climate change, because that number can be changed by taking action, Scheraga said.

"We are not saying in this report that more people will die in the future due to climate change," he said. "What we are saying is that there's an increased risk of deaths due to heat waves in the future as the climate changes.

"We have an opportunity to anticipate these increased risks ... and to due to prepare for the future in order to mitigate these risks."

Limited to climate change impacts in the United States, the report found a likely increase in food and water-borne germs as the world warms and habitat ranges expand for some disease-causing organisms.

Also, the inequities now found in the U.S. health care system are likely to be exacerbated by global warming: "Many of the expected health effects are likely to fall disproportionately on the poor, the elderly, the disabled and the uninsured."

Global warming is expected to affect water supplies across the country, with reduced water flow in rivers, lower groundwater levels and more salt creeping into coastal rivers and groundwater, the report said.

People who live along the coasts will face the consequences of rising sea levels and severe weather events while city dwellers can expect higher energy demand to cool buildings -- though the demand for heat will probably decline.

The report covers much of the same substance as an EPA document released on Monday that found global warming endangers human health. This document was part of the agency's response to a 2007 Supreme Court ruling that found the EPA had the power to regulate climate-warming greenhouse gas emissions if it was found that they hurt human health.

However, the agency has indicated no action is likely before the Bush administration leaves office next January.

Stephen Johnson, head of the environmental agency, has been called to testify on July 30 before the Senate Judiciary Committee hearing on alleged White House interference with the agency. Researchers have repeatedly complained of White House censorship of environmental science.

By Juan Bustamante

Reuters

BUENOS AIRES - Argentine scientists are taking a novel approach to studying global warming -- strapping plastic tanks to the backs of cows to collect their burps.

Researchers say the slow digestive system of cows makes them a producer of methane, a potent greenhouse gas that gets far less public attention than carbon dioxide in efforts to fight global warming.

Scientists around the world are studying the amount of methane in cow burps and Argentine researchers say they have come up with a unique way.

Attaching a red plastic tank to a cow's back and connecting it through a tube to the animal's stomach, scientists say they can trap bovine burps and analyze them.

"When we got the first results, we were surprised. Thirty percent of Argentina's (total greenhouse) emissions could be generated by cows," said Guillermo Berra, a researcher at the National Institute of Agricultural Technology.

One of the world's biggest beef producers, Argentina has some 55 million heads of cattle grazing on the famed Pampas grasslands.

Berra said the researchers "never thought" a cow weighing 550 kg (1,210 lb) could produce 800 to 1,000 liters (28 to 35 cubic feet) of emissions each day.

At least 10 cows are being studied, Berra said, including some in a corral whose burps are collected in yellow balloons hanging from the roof.

Greenhouse gases are widely blamed for causing global warming. Methane, researchers say, is 23 times more potent than carbon dioxide in trapping heat in the atmosphere and can be found in animal waste, landfills, coal mines and leaking natural gas pipes.

Scientists are working to develop new diets for cows that could make it easier for them to digest food, moving them away from grains to plants like alfalfa and clover.

"We have done a preliminary study and have found that by using tannins, you can reduce methane emissions by 25 percent," said Silvia Valtorta of the National Council of Scientific and Technical Investigations.