Characteristics of the spatiotemporal distribution of daily extreme temperature events in China:Minimum temperature records in different climate states against the background of the most probable temperature

Based on the skewed function,the most probable temperature is defined and the spatiotemporal distributions of the frequencies and strengths of extreme temperature events in different climate states over China are investigated,where the climate states are referred to as State I,State II and State III,i.e.,the daily minimum temperature records of 1961-1990,1971-2000,and 1981-2009.The results show that in space the frequency of high temperature events in summer decreases clearly in the lower and middle reaches of the Yellow River in State I and that low temperature events decrease in northern China in State II.In the present state,the frequency of high temperature events increases significantly in most areas over China except the north east,while the frequency of low temperature events decreases mainly in north China and the regions between the Yangtze River and the Yellow River.The distributions of frequencies and strengths of extreme temperature events are consistent in space.The analysis of time evolution of extreme events shows that the occurrence of high temperature events become higher with the change in state,while that of low temperature events decreases.High temperature events are becoming stronger as well and deserve to be paid special attention.

Applicability of Phase Synchronization Clustering to Detect the Process of Climate Events

Phase synchronization clustering method is used to detect the process of extreme weather events rather than extreme values events mathematically. The applicability is discussed from the aspects of noise intensity and sequence length and the observed data are applied practically. The detection process shows that clustering measure difference can detect the temporal process objectively to a certain degree and it has certain application to detect the temporal process of extreme weather events.

Detection of the Process about Extreme Weather Events

In view of extreme values events mathematically rather than the process about extreme weather events, phase synchronization clustering method is introduced and the applicability of the method is discussed from the aspects of noise intensity and sequence length. At last the observed data is applied. The results show that clustering measure difference can detect the temporal process objectively to a certain degree and it has certain application to detect the temporal proc- ess of extreme weather events.

Explore QCD phase transition with thermal photons

This pilot study was to assess the high temperature and zero baryon density region of quantum chromodynamics(QCD) phase diagram with thermal photon emission,where the nature of QCD phase transition is ambiguous.Based on a(3+1)-D ideal hydrodynamical model to describe macroscopically the collision system,thermal photons emitted from Pb+Pb collisions at 2.76 TeV are investigated.The result reveals that photons from heavy ion collisions at high energy and centrality are possible to distinguish the structure of the hot dense matter,in QGP phase or hadronic phase,thus may provide an approach to explore the nature of this finite-temperature QCD transition(that is,first-order,second-order or analytic crossover).