Sun, G., and Q. Ye, 1996: A study on the variation of drought periods occurring in northwest China and other Africa-Asia contiental regions. Acta Meteorologica Sinica, 10, 473-484.
Characteristics of the drought periods which occurred in North Africa, Middle East, middle Asia and northwest China were studied based on the analysis of rainfall data from 1870-1990. It is found that the drought periods first started in North Africa and expanded eastward to northwest China through Middle East and middle Asia in about 27.5 years. And then a new teleconnection pattern of 30-50 day low-frequency oscillation which is associated with the droughts over the Africa-Asia continent was discovered. Finally, a hypothesis is proposed based on the statistical results that the eastward expansion of drought periods may be caused by the occurrence of giant earthquakes (Ms>6.0) which have a tendency to shift eastward from North Africa to northwest China in about 27.75 years.