New advance in research on the international little ice age climate change

Abstract

The Little Ice Age (LIA) is a cold climatic event since Medieval Warm Period (MWP) and a previous period before global warming over the last 100 years. Recent years, the studies on LIA have achieved so many advances in the world by using the data such as ice core, tree-rings, stalagmite, lake sediment and historic documents, etc. The focuses of controversy about the LIA research are as follows: Is the LIA widespread climatic anomaly of last 1000 years? How long is the duration of the LIA? And does the duration have regional difference? The studies show there are three colder periods during the LIA, centered in the 15th century, the 17th century, and the 19th century on the average. The LIA is a climatic anomaly in worldwide. The time span of the LIA is about 500-600 years, but the length of the time span is not the same in different regions. The style of the dry/wet, warm/cold periods of the LIA exists regional discrepancy. Generally speaking, in the area of higher latitude and elevation, the beginning and end time of LIA is earlier than that in the area of lower latitude and elevation. And the vary argument of temperature is smaller for the latter. The formation of the LIA is impacted by the activities of volcanic and solar, the general circulation, the interaction between atmosphere and ocean, atmosphere and land surface. In this paper, integrated analysis is done by using the present research achievement about the LIA. The characteristics of the LIA of distribution in the world are given. The possible causes of the LIA are analyzed. Lastly, the main unresolved problems in the study of the LIA are proposed.