美國環境保護署於17日公佈一項數據，美國在2004年所排放的溫室效應氣體較2003年增加1.7%。英國國家科學學術研究單位「皇家學會」表示，此為有史以來單一國家最高的年度排放量，他並警告世人需迫切遏止溫室效應氣體的排放。
美國環保署署長強森（Stephen Johnson）表示，溫室氣體排放量增加主要集中發生在經濟景氣期間，主因是電力與燃料消耗增加導致二氧化碳排放量上升。
環保署該報告名為《1990-2004年美國溫室氣體排放與碳匯調查》，是美國向「聯合國氣候變化綱要公約」秘書處提交的最新年度報告。所謂氣候變化綱要公約（UNFCCC），是國際間為遏止氣候變遷所簽署訂定的合作綱要，所有締約國均須向秘書處提報類似報告。
就在美國環保署提交這份報告之前，上個月一份臨時告內容才公布最新的統計數據，顯示美國在2004至2005年間的「溫室氣體當量」微量減少30萬公噸，為6.56億公噸；不過，二氧化碳「淨排放量」仍升高約180萬公噸，是從2002年以來連年升高的第三年。
英國科學家認為，此趨勢顯示美國未能扮演國際間努力限制溫室氣體排放的龍頭角色，而且還是破壞國際合作最惡劣的國家──擁有全世界僅5%人口的美國卻製造大約所有溫室效應氣體的四分之一。
英國皇家學會副會長李德（David Read）教授說︰「如果排放量持續攀升，我們可預見世界各地會有更多的衝擊。」他警告：「開發中國家將會難以因應氣候變遷帶來的挑戰，佔溫室氣體排放大宗的主要工業國家應體認到，發展中國家也必努力適應世界環境變化──例如海平面上升幾公尺這件事。」
美國環保署的這份報稿已上網公告，可點選瀏覽。
U.S. greenhouse gas emissions during 2004 increased by 1.7 percent from the previous year, according to the U.S. Environmental Protection Agency, 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.
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 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.
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.
"If emissions continue to rise, we can expect even more impacts across the world," vice-president of the Royal Society, Professor David 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 realize that they would also struggle to adapt to a world in which, for instance, sea levels are several meters higher."
To read the report, "Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2004," online, click here.
