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 period...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 Con- tinent was discovered.Finally,a hypothesis is proposed based on the statistical results that the east- ward 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.展开更多
文摘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 Con- tinent was discovered.Finally,a hypothesis is proposed based on the statistical results that the east- ward 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.
