McConnell Joseph R, Aristarain Alberto J, Banta J Ryan, Edwards P Ross, Simões Jefferson C
Desert Research Institute, Nevada System of Higher Education, Reno, NV 89512, USA.
Proc Natl Acad Sci U S A. 2007 Apr 3;104(14):5743-8. doi: 10.1073/pnas.0607657104. Epub 2007 Mar 26.
Crustal dust in the atmosphere impacts Earth's radiative forcing directly by modifying the radiation budget and affecting cloud nucleation and optical properties, and indirectly through ocean fertilization, which alters carbon sequestration. Increased dust in the atmosphere has been linked to decreased global air temperature in past ice core studies of glacial to interglacial transitions. We present a continuous ice core record of aluminum deposition during recent centuries in the northern Antarctic Peninsula, the most rapidly warming region of the Southern Hemisphere; such a record has not been reported previously. This record shows that aluminosilicate dust deposition more than doubled during the 20th century, coincident with the approximately 1 degrees C Southern Hemisphere warming: a pattern in parallel with increasing air temperatures, decreasing relative humidity, and widespread desertification in Patagonia and northern Argentina. These results have far-reaching implications for understanding the forces driving dust generation and impacts of changing dust levels on climate both in the recent past and future.
大气中的地壳尘埃通过改变辐射收支、影响云的成核作用和光学特性直接影响地球的辐射强迫,并通过海洋施肥间接影响地球的辐射强迫,而海洋施肥会改变碳固存。在过去关于冰川到间冰期过渡的冰芯研究中,大气中尘埃增加与全球气温下降有关。我们展示了南极半岛北部近几个世纪铝沉积的连续冰芯记录,南极半岛是南半球变暖最快的地区;此前尚未有这样的记录被报道。该记录显示,在20世纪,铝硅酸盐尘埃沉积增加了一倍多,这与南半球约1摄氏度的变暖同时发生:这种模式与气温升高、相对湿度降低以及巴塔哥尼亚和阿根廷北部普遍的沙漠化情况并行。这些结果对于理解驱动尘埃产生的力量以及过去和未来尘埃水平变化对气候的影响具有深远意义。