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1.
正Convection and its ensuing severe weather,such as heavy rainfall,hail,tornado,and high wind,have significant impacts on our society and economy(e.g.,Cao et al.,2004;Fritsch and Carbone,2004;Verbout et al.,2006;Ashley and Black,2008;Cao,2008;Cao and Ma,2009;Zhang et al.,2014).Due to its localized and transient nature,the initiation of convection or convective initiation remains one of the least  相似文献   

2.
The long-term warming of the ocean is a critical indicator of both the past and present state of the climate system. It also provides insights about the changes to come, owing to the persistence of both decadal variations and secular trends,which the ocean records extremely well(Hansen et al., 2011;IPCC, 2013;Rhein et al., 2013;Trenberth et al., 2016;Abram et al., 2019).  相似文献   

3.
Along with anthropogenic global warming,the Northern Hemisphere(NH)has experienced more frequent cold air out-breaks and heavy snowfalls in recent decades(Petoukhov and Semenov,2010;Liu et al.,2012;Cohen et al.,2014;2020;Overland et al.,2015).The most recent example of extreme winter weather was the extreme cold events that occurred from East Asia to North America during the winter of 2020/21(Cohen et al.,2021;Zheng et al.,2022a).  相似文献   

4.
1. IntroductionAccording to the reconstruction of paleo-temperature based on δ18 O data of ice core in theGreenland (see Jouzel et al., 1987; Grootes et al.,1993; Blunier and Brook, 2001), the current inter-glacial epoch, the Holocene, began at ca. 11.5 thou-sand years before present (ka BP). Multiple sources(pollen data, macrofossils) reveal that the summer cli-mate in the Northern Hemisphere was warmer in theearly to middle Holocene (MH) (ca. 8-6ka BP) relativeto the present climate. …  相似文献   

5.
1. Introduction The Ertel (1942) potential vorticity (PV) has beenwidely used, especially in the studies of large-scale sys-tems (Hoskins et al., 1985; McIntyre and Norton, 2000;Wu et al., 1995; Wu and Liu, 1999). The vorticityequation in quasi-geostrophic ?ows only predicts thevariation of the vorticity and cannot provide a usefulconstraint to the vorticity. PV provides a constraintfor the variation of the vorticity in the baroclinic at-mosphere (Gao et al., 1990). The PV may not bec…  相似文献   

6.
1. IntroductionBecause the South China Sea (SCS) is one of theregions where the Asian summer monsoon onset oc-curs earliest, the SCS summer monsoon (SCSSM) hasalways been a research focus, especially in recent yearswith the implementation of the SCS Monsoon Exper-iment (SCSMEX) (e.g., Tao and Chen, 1987; Changand Chen, 1995; Lau et al., 2000; Ding and Li, 1999;Ding and Liu, 2001; Li and Wu, 2000; Xie et al., 1998;Zhang et al., 2004). Climatologically, the SCSSM on-set is a rem…  相似文献   

7.
With the high-speed development of numerical weather prediction, since the later 1980’s, the prediction of short-range climate anomalies has attracted worldwide meteorologists’ attention. What the so called short-range re-fers to the time scale from one month to one season or more. In dealing with the problem of short-range climate pre-diction, two points are needed noticing: one is the basic research to explore or investigate the mechanism of variability of the slow varying components which mainly include internal dynamics of extratropics, external forcings and tropical dynamics, and the other is the modeling efforts to simulate the process of the long-term evolution of the signal which include the improvement of model quality, stochastic prediction and the air-sea-coupled model (Miyakoda et al.,1986). Previous researches on the numerical prediction of short-term climate anomalies are mostly concentrated in the analysis of variables with global spatial scale, especially the global general atmospheric circulation analysis.As to the simulation or prediction of regional short-term climate anomalies, there exist many difficulties and problems. Though some meteorologists are devoting themself to this field, up to now, they have not reached satisfac-tory results. As a primary effort, by using the 2-level general atmospheric circulation model developed in the Institute of Atmospheric Physics, Chinese Academy of Sciences (IAP-AGCM) (Zeng et al., 1989), and taking the year of 1985 as a case, a numerical simulation of regional short-term climate change is completed. We pay high attention to the predictand of anomalous summer rainfall in the Yangtze River and Yellow River valleys, especially its month-to-month variation.  相似文献   

8.
1. Introduction As an important way to study the global climate change, because of its low resolution, GCM (general circulation model) shows obvious deficiency and uncer- tainty in capturing some regional features when used in the regional climate study, and the uncertainty is even serious in regional climate simulation over East Asia (Ding et al., 2000; Zhao and Luo, 1998; Qian et al., 1999). The high-resolution regional climate model (RegCM) developed in the 1980s can provide better simu…  相似文献   

9.
Ⅰ.INTRODUCTION We have discovered that there exists a good corresponding relationship between theanomalous axes of soil temperature at a depth of 1.6m in winter (December to February) andprecipitations in following flood season (Tang et al., 1982a). We have also designed a simplethermodynamical model and applied it to the forecasting of precipitations in the flood season(Tang et al., 1982 b,c). The practical forecast started from 1975. Before 1980, however, therewere only 40-50 stations in China for measuring the soil temperature at a 1.6m depth. Since1980, the stations have been increased to a total of about 180, but no available mean valueshad been obtained from newly added stations before 1982. Therefore the analysis and map-ping of anomalies of soil temperature was not performed until 1983, and from then on theprecision of analysis has been greatly improved. The following is the actual situation of forecast in five years from 1983 to 1987.  相似文献   

10.
The increasing heat-trapping gases emitted by human activities into the atmosphere produce an energy imbalance between incoming solar radiation and outgoing longwave radiation that leads to global heating(Rhein et al.,2013;Trenberth et al.,2014;von Schuckmann et al.,2016).The vast majority of global warming heat ends up deposited in the world’s oceans,and ocean heat content(OHC)change is one of the best—if not the best—metric for climate change(Cheng et al.,2019).In 2018,continued record heat was measured in the Earth’s climate system.In fact,2018 has set a new record of ocean heating,surpassing 2017,which was the previous warmest year ever recorded(Cheng et al.,2018)(Fig.1).  相似文献   

11.
1. Introduction South Asian monson is an important weather and climate phenomenon, and it is also an important con- stituent of the global atmospheric circulation, thus people pay more attention to it (Hahn and Manabe, 1975; Zhu and Zhao, 1987; Zhu et al., 1991; Zhou and Yang, 1994; Wu and Huang, 2001; Li et al., 1999). For example, Zhu and Zhao (1987) studied the effects of terrain on South Asian monsoon by the equato- rial atmospheric balance model, indicating that ter- rain effect is …  相似文献   

12.
Synoptic Features of the Second Meiyu Period in 1998 over China   总被引:10,自引:0,他引:10  
1. IntroductionThe Meiyu, translated as plum rain, is a majorannual rainfall event over the Yangtze River Basin inChina and southern Japan in June and July. Theheavy rainfall is mainly caused by a quasi-stationaryfront, known as the Meiyu front, extended from east-ern China to southern Japan (Tao, 1958; Matsumotoet al., 1971; Akiyama, 1990; Gao et al, 1990). Studiesof Zhang and Zhang (1990) and Chen et al. (1998)pointed that the Meiyu front is one of the most signif-icant circulation s…  相似文献   

13.
The Antarctic,including the continent of Antarctica and the Southern Ocean,is a critically important part of the Earth system.Research in Antarctic meteorology and climate has always been a challenging endeavor.Studying and predicting weather patterns in the Antarctic are important for understanding their role in local-to-global processes and facilitating field studies and logistical operations in the Antarctic(e.g.,Walsh et al.,2018).Studies of climate change in the Antarctic are comparatively neglected compared to those of the Arctic.However,significant climate changes have occurred in the Antarctic in the past several decades,i.e.,a strong warming over the Antarctic Peninsula even with a recent minor cooling,a deepening of the Amundsen Sea low,a rapid warming of the upper ocean north of the circumpolar current,an increase of Antarctic sea ice since the late 1970s followed by a recent rapid decrease,and an accelerated ice loss from the Antarctic ice shelf/sheet since the late 1970s(e.g.,Turner et al.,2005;Raphael et al.,2016;Sallée,2018;Parkinson,2019;Rignot et al.,2019).Investigating recent climate change in the Antarctic and the underlying mechanisms are important for predicting future climate change and providing information to policymakers.  相似文献   

14.
1 INTRODUCTIONIn order to gain further insight into the nature of decadal- scale climate variability at highlatitudes( e.g.,Mysak et al.,1 990 ;Deser and black- mon,1 993) ,there have been a number ofrecent model studies of sea ice- thermohaline circulation interactions which exhibitoscillationson this timescale( Yang and Neelin,1 993;Zhang et al.,1 995 ;Yang and Huang,1 996 ) .Acommon feature of these studies is that the ocean models are integrated using mixedboundary conditions( MBC…  相似文献   

15.
正1.Introduction Historic instrumental weather observations,made on land or at sea from as early as the 17th century(e.g.,Camuffo et al.,2010),are integral to extending our understanding of the decadal and centennial variations of Earth’s climate and for comparison with paleo-proxy data.The potential of such data is shown to best effect when used in dynamical 4D global  相似文献   

16.
1.Overview In July 2018,the Antarctic community came together to meet at the 13th Workshop on Antarctic Meteorology and Climate(WAMC)in Madison,Wisconsin,USA(Fig.1);and in the following year in June 2019,the 14th WAMC was held in Charleston,South Carolina,USA(Fig.2).With a growing history,the WAMC addresses the topics of Antarctic meteorology and climate(Kameda et al.,2008;Colwell et al.,2016;Lazzara et al.,2018)as well as weather-related issues of scientific and operational support.The workshops bring together researchers,operational forecasters,numerical modelers,observational specialists,and students.The themes of both workshops included Antarctic meteorological observations,Antarctic atmospheric numerical modeling,Antarctic meteorological and climate research,and Antarctic weather forecasting and operational services.The 2018 and 2019 WAMC were both followed by a one-day focus on the Year of Polar Prediction-Southern Hemisphere(YOPP-SH),when preparations and follow-up discussions were made with regard to the YOPP Special Observing Period from 16 November 2018 to 15 February 2019.  相似文献   

17.
1. IntroductionInvestigations about atmospheric LFW have been a focus of research since Madden andJulian/s outstanding analysis works (1971, 1972). Many dynamical and thermal mechanisms(Chao et al., 1996; Fu et al., 1998; Hendon et al., 1998; Krishnamurti et al., 1988; Lau andChan, 1988) have been advised to explain LFW. Among them are oceanic effects, such as SSTeffect, thermal forcing and others. Usually atmosphere and ocean are taken as a coupled system, which is used to explain ENS…  相似文献   

18.
Ice nuclei-supersaturation spectra in the form of a Power Law ( Ni=RSir; B and y are empirical constants) have been expressed since 1973 when the curve was first introduced independentally by Gagin and Huffman. Experiments performed with a thermal gradient diffusion chamber in order to investigate the validity of the power curve. The results show that a linear curve fit to the data is as good as the power curve. The linear curve has the coefficients of correlation between 0.75 and 0.93 whereas the power curve fit to the same data has the coefficients between 0.82 and 0.93. The data reported by other workers, Zamurs and Jiusto and Zamurs et al., exhibit the same trend.  相似文献   

19.
In this paper,by using measurements in micrometeorology and radiation balance in the surface layer(Yamanouchiet al.,1981;Wada et al.,1981;Ishikawa et al.,1982;Ohata et al.,1983),we have analyzed the diurnal and annual varia-tion characteristics of radiation balance in spring,summer,autumn and winter,and calculated the momentum flux andsensible heat flux with the aerodynamic method and profile gradient alternate method in different seasons.We have alsoobtained the diurnal variation characters of the latent heat flux from the equation for energy balance.The results fromthe calculation are compared.Finally,the relationship between the turbulent heat and momentum exchange coefficientand the diurnal variation of the Richardson number is discussed.  相似文献   

20.
Human-emitted greenhouse gases(GHGs)have resulted in a long-term and unequivocal warming of the planet(IPCC,2019).More than 90%of the excess heat is stored within the world's oceans,where it accumulates and causes increases in ocean temperature(Rhein et al.,2013;Abram et al.,2019).  相似文献   

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