座位於紐約市的「美國太空總署哥達德太空研究院」（GISS）24日公布一則消息，2008年為2000年以來地表溫度最低的一年。
不過研究人員們接著指出，即便如此，全球暖化依舊不減其威脅性。人類自1880年起開始使用儀器逐年記錄溫度的變化，而2008年則排名記錄迄今溫度最高的第9名。記錄中前10名均溫最高的年度主要分佈在1997至2008年之間。
GISS院長韓森（James Hansen）博士表示，2008年均溫偏向涼爽是因為該年太陽的週期正值活動極小期，是10到12年為一週期的電磁活動中的最低點，因此照射向地球的輻射能量明顯不如往年。
GISS研究的基準線是以1951至1980年間的均溫為準，而2008年所測得的地球表面平均溫度高出標準值0.44°C。
當年世界各地的氣溫不是接近標準就是高出標準一些。諸如歐亞大陸、北極圈和南極洲半島在記錄中溫度略高，不過許多太平洋地區的溫度則低於過去長年均溫。
研究團隊指出，2008年太平洋熱帶地區溫度相對較低，主要是在前半年受反聖嬰現象的影響所致。
聖嬰與反聖嬰現象是過去數年來發生在太平洋地區的兩個相反狀態，讓赤道附近的海面溫度出現自然振盪。反聖嬰現象比正常溫度要低；相反地，典型的聖嬰則是在反聖嬰之後1至2年內出現的暖化現象。
美國國土在2008年的均溫相當接近1951至1980年之間的標準值，民眾皆可感受到當年的溫度較過去10年涼爽的多。
韓森表示，「儘管太陽輻射減弱有助降低地表溫度，不過下一波聖嬰現象預計將發生在2009或2010年，因此在接下來的1至2年內地球表面最高溫的記錄很有可能被突破」。
韓森早在2008年1月即曾準確預測，「2008年將未必是地球平均溫度例外的一年。」「即便不考慮大量的火山爆發運動，隨著下波聖嬰現象的來臨，2005年地球最高均溫的記錄將可能在未來幾年內被打破，因為這些暖化的因素都將促成溫室氣體不斷增加」。
韓森緊接著說道，「如我們於2008年時所預測一般，2007年均溫果真高於2006年，而過去30年來的暖化趨勢無疑地助長了人為溫室氣體增加的效果」。
Climatologists at the NASA Goddard Institute for Space Studies in New York City said today that 2008 was the planet's coolest year since 2000.
Yet this does not mean that global warming is no longer a threat, they said. The analysis also showed that 2008 was the ninth warmest year since continuous instrumental records were started in 1880. The 10 warmest years on record have all occurred between 1997 and 2008.
Dr. James Hansen, director of the Goddard Institute, says the Earth's cooler temperature last year is due in part to the fact that the Sun is just passing through solar minimum, the low point in its 10 to 12 year cycle of electromagnetic activity, when it transmits its lowest amount of radiant energy toward Earth.
The GISS analysis found that the global average surface air temperature was 0.44°C above the global mean for 1951 to 1980, the baseline period for the study.
Most of the world was either near normal or warmer in 2008 than the norm. Eurasia, the Arctic, and the Antarctic Peninsula were exceptionally warm, while much of the Pacific Ocean was cooler than the long-term average.
The relatively low temperature in the tropical Pacific was due to a strong La Nina that existed in the first half of the year, the research team observed.
La Nina and El Nino are opposite phases of a natural oscillation of equatorial Pacific Ocean temperatures over several years. La Nina is the cool phase. The warmer El Nino phase typically follows within a year or two of La Nina.
The temperature in the United States in 2008 was not much different than the 1951-1980 mean, which makes it cooler than all the previous years this decade.
"Given our expectation that the next El Nino will begin this year or in 2010, it still seems likely that a new global surface air temperature record will be set within the next one to two years, despite the moderate cooling effect of reduced solar irradiance," said Hansen.
"It is unlikely that 2008 will be a year with truly exceptional global mean temperature," Hansen correctly predicted in January 2008. "Barring a large volcanic eruption, a record global temperature clearly exceeding that of 2005 can be expected within the next few years, at the time of the next El Nino, because of the background warming trend attributable to continuing increases of greenhouse gases."
"As we predicted last year," Hansen said then, "2007 was warmer than 2006, continuing the strong warming trend of the past 30 years that has been confidently attributed to the effect of increasing human-made greenhouse gases."
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In my healing journey and learning to attain the breath awareness, I become aware of the reality that all the creatures of the world are breathing the same breath. Take action, here and now. From my physical being to the every corner of this out of balance's planet.
