Chen Junye, Carlson Barbara E, Del Genio Anthony D
Department of Earth and Environmental Sciences, Columbia University, Palisades, NY 10964, USA.
Science. 2002 Feb 1;295(5556):838-41. doi: 10.1126/science.1065835.
Satellite observations suggest that the thermal radiation emitted by Earth to space increased by more than 5 watts per square meter, while reflected sunlight decreased by less than 2 watts per square meter, in the tropics over the period 1985-2000, with most of the increase occurring after 1990. By analyzing temporal changes in the frequency of occurrence of emitted thermal and reflected solar fluxes, the effects of El Niño-Southern Oscillation are minimized, and an independent longer-time-scale variation of the radiation budget is identified. Similar analyses of upper tropospheric humidity, cloud amount, surface air temperature, and vertical velocity confirm that these flux changes are associated with a decadal-time-scale strengthening of the tropical Hadley and Walker circulations. Equatorial convective regions have intensified in upward motion and moistened, while both the equatorial and subtropical subsidence regions have become drier and less cloudy.
卫星观测表明，在1985年至2000年期间，热带地区地球向太空发射的热辐射每平方米增加了5瓦以上，而反射阳光每平方米减少了不到2瓦，大部分增加发生在1990年之后。通过分析发射的热通量和反射的太阳通量出现频率的时间变化，厄尔尼诺-南方涛动的影响被最小化，并且确定了辐射收支的一个独立的较长时间尺度变化。对对流层上层湿度、云量、地面气温和垂直速度的类似分析证实，这些通量变化与热带哈得莱环流和沃克环流十年时间尺度的加强有关。赤道对流区域的上升运动增强且湿度增加，而赤道和副热带下沉区域都变得更干燥且云量减少。
