Global warminghiatushas attracted much attention since it was put forward,which is a hot issue in the field of global climate change.It is mainly manifested by the lower warming rate of the global mean air surface temperature than before during 1998-2012.Besides,the atmospheric circulation and ocean circulation have also changed significantly.In the attribution analysis of global warminghiatus,many scientists believe that the Pacific Decadal Oscillation plays an important role.Other possible factors may include changes of the Atlantic meridional overturning circulation and Antarctic Bottom Water.However,there are biases in temporal consistence and spatial coverage of observation data,which increase the uncertainty of global warminghiatus.Nevertheless,it is the consensus of many scientists that the internal variability of the climate system changed and then led to the increased absorption of heat in the deep ocean.If the uncertainty of the global warming hiatus is hoped to be resolved, the enrichment and improvement of observation data is a tough requirement.