Extreme events of weather and climate happened frequently over the world in 2011. The longest cold snap since 1945 impacted the Korean peninsula in January. At the same time, the strong winter storm with snowy weather impacted 100 million people across the United States. Storms and heavy monsoonal rains from July to October contributed to the worst flooding in Thailand since 1942. Crippling drought gripped East Africa and Cuba in South America. A freak sandstorm driven by extremely dry conditions and strong winds swept across the town of Rostock in the northern part of Germany on 8 April. Arctic sea-ice volume was estimated at a new lowest record in September. The number of high temperature days in China during the period of May to September in 2011 ranked the second since 1961 and the maximum temperature records were broken in many stations. The annual precipitation is the lowest in recent 60 years, which led to the extreme drought in many regions of China. Severe autumn flood happened in western China and Huanghe River-Huaihe River basins.