Record Increase in U.S. Greenhouse Gas Emissions Reported

WASHINGTON, DC, April 18, 2006 (ENS) - U.S. greenhouse gas emissions during 2004 increased by 1.7 percent from the previous year, according to the U.S. Environmental Protection Agency (EPA), which released the figures Monday. This was the largest annual amount ever produced by any country on record, said The Royal Society, the UK national academy of science, warning that urgent action is needed to curb emissions.

The increase, which occurred during a period of economic expansion, was due primarily to an increase in carbon dioxide (CO2) emissions associated with fuel and electricity consumption, said EPA Administrator Stephen Johnson.


Stephen Johnson is administrator of the U.S. Environmental Protection Agency. (Photo courtesy Taylor U.)
"The Bush administration has an unparalleled financial, international and domestic commitment to the reduction of greenhouse gas emissions," Johnson said, attempting to present the record U.S. emission levels in the best possible light.

The U.S. report shows that levels of two other greenhouse gases - methane and nitrous oxide - have decreased from 1990 levels by 10 percent and two percent, respectively.

The report, "Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2004," is the latest in an annual set of reports that the United States submits to the Secretariat of the United Nations Framework Convention on Climate Change, a treaty which sets an overall framework for intergovernmental efforts to limit climate change. All nations that are Parties to the treaty submit such reports.

The U.S. report follows publication last month of provisional figures showing that greenhouse gas emissions in the UK fell slightly by 0.3 million metric tons to 656.0 million metric tons of carbon dioxide equivalent between 2004 and 2005. However, net emissions of carbon dioxide increased by about 1.8 million metric tons, the third consecutive annual rise since 2002.

s British scientists said the increase shows that the United States is failing to spearhead the international effort to limit emissions of these gases, although it is the worst offender. With about five percent of the world's population, the United States produces roughly one-quarter of all global greenhouse gas emissions.

A top scientist with The Royal Society today called for immediate action by the United States and Britain to cut greenhouse gas levels, and to honor their commitments under the UN climate change treaty.

Professor David Read, vice-president of the Royal Society, said, “The figures published this week show not only that U.S. emissions are not decreasing, but that they are actually increasing on an annual basis. And while the UK appears to be doing slightly better, its carbon dioxide emissions have been rising annually for the last three years."


Professor David Read is vice-president of the Royal Society. (Photo courtesy Royal Society)
“Carbon dioxide levels in the atmosphere are rising rapidly," said Read, a biologist and ecologist. "They are now about a third higher than they were before the start of the Industrial Revolution in the 18th century, and probably higher than they have been for at least 10 million years."

"If we were to stabilize carbon dioxide levels at twice pre-industrial levels, countries like the UK and U.S. would need to reduce emissions by about 60 percent by the middle of this century," he said.

The rise of 110 million metric tons in annual emissions between 2003 and 2004 was the biggest for the United States since 2000, Read points out.

Johnson said the United States is working to limit greenhouse gas emissions. "Even with a dramatic increase in economic activity," he said, "the U.S. is making significant progress toward the President's greenhouse gas reduction goals by working with our partners to reduce their climate footprints in cost-effective ways, both at home and abroad."

The report states that the causes of U.S. greenhouse gas emissions are robust economic growth in 2004, leading to increased demand for electricity and fossil fuels; expanding industrial production in energy-intensive industries, also increasing demand for electricity and fossil fuels; increased travel, leading to higher rates of consumption of petroleum fuels.


Rush hour traffic in San Diego, California. More gasoline powered cars on the road means more carbon dioxide and nitrous oxide emitted into the atmosphere. (Photo by Peter Sobczak courtesy Polonia San Diego)
The primary greenhouse gas emitted by human activities in the United States was carbon dioxide, representing about 85 percent of total greenhouse gas emissions. The largest source of CO2, and of overall greenhouse gas emissions, was fossil fuel combustion.

While CO2 is the most prevalent greenhouse gas, there are others that trap more heat close to the planet, raising the global temperature. The EPA report quotes the Intergovernmental Panel on Climate Change (IPCC) composed of more than 2,500 scientists, as saying methane is more than 20 times as effective as CO2 at trapping heat in the atmosphere.

Over the last 250 years, the concentration of CH4 in the atmosphere increased by 143 percent. Experts believe that over half of this atmospheric increase was due to emissions from human sources, such as landfills, natural gas and petroleum systems, agricultural activities, coal mining, wastewater treatment, stationary and mobile combustion, and certain industrial processes.

In the United States, the EPA report shows, methane, emissions, which have steadily declined since 1990, resulted primarily from decomposition of wastes in landfills, natural gas systems, and enteric fermentation associated with domestic livestock.

While total nitrous oxide (N2O) emissions are much lower than carbon dioxide emissions, N2O is approximately 300 times more powerful than CO2 at trapping heat in the atmosphere.

Since 1750, the global atmospheric concentration of nitrous oxide has risen by approximately 18 percent.

In the United States, agricultural soil management and mobile source fossil fuel combustion were the major sources of nitrous oxide emissions.

HFCs and PFCs are families of synthetic chemicals that are being used as alternatives to the ozone depleting substances, which are being phased out under the Montreal Protocol and Clean Air Act Amendments of 1990.

HFCs and PFCs do not deplete the stratospheric ozone layer, and are therefore acceptable alternatives under the Montreal Protocol.

But these compounds, along with sulfur hexafluoride (SF6), are potent greenhouse gases. Sulfur hexafluoride is the most potent greenhouse gas the IPCC has evaluated.

In addition to having high global warming potentials, SF6 and PFCs have extremely long atmospheric lifetimes, resulting in their essentially irreversible accumulation in the atmosphere once emitted.


The U.S. electricity transmission and distribution system has grown into a complex network containing millions of miles of wire and millions of transformers, switches, protection devices, meters, insulators, and poles. (Photo by Warren Gretz courtesy NREL)
These gases are emitted during HCFC-22 production, electrical transmission and distribution systems, semiconductor manufacturing, aluminum production, and magnesium production and processing.

Electrical transmission and distribution systems accounted for most SF6 emissions, the EPA report states.

Professor Read said, “According to the World Meteorological Organization, the global average temperature in 2005 was the second highest since records began in 1861. Eight of the 10 warmest years have occurred since 1995. The scientific evidence suggests that rising levels of carbon dioxide and other greenhouse gases will cause temperatures to rise further, causing a range of climate effects and making our oceans more acidic."

"There is already evidence that suggests we are seeing some of those climate effects, such as a study by U.S. researchers last year that linked a drop in annual rainfall in East Africa with rising surface water temperatures in the Indian Ocean," the British scientist said.

“If emissions continue to rise, we can expect even more impacts across the world," Read warned. "The developing world will find it difficult to adapt to climate change, and the industrialized countries, which are primarily responsible for the rise in greenhouse gas levels, should realiae that they would also struggle to adapt to a world in which, for instance, sea levels are several meters higher."

"The science justifies action now by all countries to both adapt to climate change and to reduce greenhouse gas emissions.”

To read the report, ""Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2004," online, click here.