Why is there a national drought this year?

According to the Oriental Morning Post, Zhang Peiqun, director of the Climate Prediction Office of the National Climate Center, said on February 6 that the root cause of the severe drought in the north in the past four months was the * * * interaction between La Nina and global atmospheric circulation anomalies. Zhang Peiqun, director of the Climate Prediction Office of the National Climate Center, said yesterday that the root cause of the severe drought in northern China in the past four months was the * * * interaction between La Nina and global atmospheric circulation anomalies. Drought is related to climate warming. Zhang Peiqun said that since this winter, the warm and humid air flow from the northwest Pacific in the southeast and the warm and humid air flow from the Indian Ocean and the Bay of Bengal in the southwest are less, and the fundamental reason is related to La Nina phenomenon. "La Nina phenomenon leads to the weak transport capacity of the southeast and southwest water vapor routes, which directly causes the drought in northern China." In addition, Zhai Panmao, director of the Disaster Reduction Department of China Meteorological Bureau, said at a news conference yesterday that this rare large-scale drought has something to do with long-term climate change. "A key feature of climate change is climate warming, especially in the northern region. Climate warming has intensified the development of drought. " "The occurrence of this drought is actually a persistent drought in the context of persistent drought in the north after the 1980 s. It should be said that it is in this long-term change background." Zhai Panmao said. The National Climate Center, which had little effect on the drought, said that the La Ni? a event that caused the freezing rain and snow disaster in southern China from April to May last year had basically ended, but the SST in the Middle East and the Pacific dropped again in September, and the La Ni? a state continued to be maintained. "However, this does not mean that another La Nina event has been formed." Zhang Peiqun said that there are two criteria for judging La Nina events. First, the SST in the equatorial Pacific in the Middle East is lower than 0.5℃, and second, this state will be maintained for 5-6 months. When answering a reporter's question about whether the drought will cause other side effects, such as the increase of typhoons or other extreme weather in the south, and whether the drought will continue in the second half of this year, Zhai Panmao said that the above situation is unlikely, but it is necessary to guard against drought-related disasters, such as forest fires and wheat pests and diseases.