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1.
ＡＦｉｎｉｔｅ－ＭｏｄｅＭｏｄｅｌｏｆＩｄｅａｌＦｌｕｉｄＤｙｎａｍｉｃｓｏｎｔｈｅ２－ＳｐｈｅｒｅＷｅｉＭｏｚｈｅｎｇＣＲＣｆｏｒＳｏｕｔｈｅｒｎＨｅｍｉｓｐｈｅｒｅＭｅｔｅｏｒｏｌｏｇｙＣＳＩＲＯＤｉｖｉｓｉｏｎｏｆＡｔｍｏｓｐｈｅｒｉｃＲｅｓｅ...  相似文献   

2.
ＣｌｉｍａｔｏｌｏｇｙａｎｄＩｎｔｅｒａｎｎｕａｌＶａｒｉａｂｉｌｉｔｙｏｆｔｈｅＳｏｕｔｈｅａｓｔＡｓｉａｎＳｕｍｍｅｒＭｏｎｓｏｏｎＫ．－Ｍ．ＬａｕＬａｂｏｒａｔｏｒｙｆｏｒＡｔｍｏｓｐｈｅｒｅｓ，Ｃｏｄｅ９１３，ＮＡＳＡ－ＧｏｄｄａｒｄＳｐａｃ...  相似文献   

3.
１．ＢａｃｋｇｒｏｕｎｄＡｇｌｏｂａｌｏｃｅａｎ－ａｔｍｏｓｐｈｅｒｅ－ｌａｎｄｓｙｓｔｅｍｇｅｎｅｒａｌｃｉｒｃｕｌａｔｉｏｎｍｏｄｅｌ（ＧＣＭ）ｈａｓｂｅｅｎｄｅｖｅｌｏｐｅｄｉｎｔｈｅＳｔａｔｅＬａｂｏｒａｔｏｒｙｏｆＮｕｍｅｒｉｃａｌＭｏｄ...  相似文献   

4.
ＳｏｍｅＡｓｐｅｃｔｓｏｆｔｈｅＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＭｏｎｓｏｏｎＤｉｓｔｕｒｂａｎｃｅｓＵｓｉｎｇａＣｏｍｂｉｎｅｄＢａｒｏｔｒｏｐｉｃ－ＢａｒｏｃｌｉｎｉｃＭｏｄｅｌ￥Ｎ．Ｒ．ＰａｒｉｊａａｎｄＳ．Ｋ．Ｄａｓｈ（ＣｅｎｔｒｅｆｏｒＡ...  相似文献   

5.
ＴｈｅＩｎｆｌｕｅｎｃｅｏｆＣｈａｎｇｅｓｉｎＶｅｇｅｔａｔｉｏｎＴｙｐｅｏｎｔｈｅＳｕｒｆａｃｅＥｎｅｒｇｙＢｕｄｇｅｔ￥ＲｕｎｈｕａＹａｎｇ；Ｊ．Ｓｈｕｋｌａ，（ＣｅｎｔｅｒｆｏｒＯｃｅａｎ－Ｌａｎｄ－ＡｔｍｏｓｐｈｅｒｅＳｔｕｄｉｅｓ４０４１Ｐ...  相似文献   

6.
ＴｈｅＥｆｆｅｃｔｏｆＷｅａｋＳｈｅａｒ－ｉｎｄｕｃｅｄＭｏｔｉｏｎｏｎＢｒｏｗｎｉａｎＣｏａｇｕｌａｔｉｏｎｏｆＡｅｒｏｓｏｌＰａｒｔｉｃｌｅｓＷｉｎｊｉｎｇｓｏｎｓ（Ｃ．Ｓ．Ｗｉｎ）（温景嵩）（Ｄｅｐａｒｔｍｅｎｔｏｆｐｈｙｓｉｃｓ，Ｎａｎｋａｉ...  相似文献   

7.
ＲｅｇｉｏｎａｌａｎｄＳｙｎｏｐｔｉｃ－ｓｃａｌｅＦｅａｔｕｒｅｓＡｓｏｃｉａｔｅｄｗｉｔｈＩｎａｃｔｉｖｅＰｅｒｉｏｄｓｏｆｔｈｅＳｕｍｍｅｒＭｏｎｓｏｏｎｏｖｅｒＳｏｕｔｈＣｈｉｎａ①Ｃ．Ｈ．ＳｏａｎｄＪｏｈｎｎｙＣ．Ｌ．ＣｈａｎＤｅｐａｒｔｍｅ...  相似文献   

8.
Ｅｆｆｅｃｔｓ　ｏｆ　Ｌａｎｄ－Ｓｅａ　Ｄｉｓｔｒｉｂｕｔｉｏｎ，　Ｔｏｐｏｇｒａｐｈｙ　ａｎｄ　Ｄｉｕｒｎａｌ　Ｃｈａｎｇｅ　ｏｎ　Ｓｕｍｍｅｒ　Ｍｏｎｓｏｏｎ　ＭｏｄｅｌｉｎｇＷａｎｓＱｉａｎｑｉａｎ（ＮａｍｉｎｇＩｎｓｔｉｔｕｔｅｏｆＭｅｔｅｏ...  相似文献   

9.
ＴｅｌｅｃｏｎｎｅｃｔｉｏｎＰａｔｅｒｎｓｉｎｔｈｅＮｏｒｔｈｅｒｎＨｅｍｉｓｐｈｅｒｅＳｉｍｕｌａｔｅｄｂｙＩＡＰＧＣＭＸｕｅＦｅｎｇ（薛峰）ａｎｄＺｅｎｇＱｉｎｇｃｕｎ（曾庆存）ＩｎｓｔｉｔｕｔｅｏｆＡｔｍｏｓｐｈｅｒｉｃＰｈｙｓｉｃｓ，Ｃｈｉｎ...  相似文献   

10.
ＥｆｆｅｃｔｏｆｔｈｅＩｎｔｅｒａｃｔｉｏｎｏｆＤｉｆｆｅｒｅｎｔＳｃａｌｅＶｏｒｔｉｃｅｓｏｎｔｈｅＳｔｒｕｃｔｕｒｅａｎｄＭｏｔｉｏｎｏｆＴｙｐｈｏｏｎｓＣｈｅｎＬｉａｎｓｈｏｕ（陈联寿）（ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＭｅｔ６ｏｒｏｌｏｇｉｃ...  相似文献   

11.
The variance of the North Atlantic Oscillation index (denoted N) is shown to depend on its coupling with area-averaged sea ice concentration anomalies in and around the Barents Sea (index denoted B). The observed form of this coupling is a negative feedback whereby positive N tends to produce negative B, which in turn forces negative N. The effects of this feedback in the system are examined by modifying the feedback in two modeling frameworks: a statistical vector autoregressive model (F VAR) and an atmospheric global climate model (F CAM) customized so that sea ice anomalies on the lower boundary are stochastic with adjustable sensitivity to the model??s evolving N. Experiments show that the variance of N decreases nearly linearly with the sensitivity of B to N, where the sensitivity is a measure of the negative feedback strength. Given that the sea ice concentration field has anomalies, the variance of N goes down as these anomalies become more sensitive to N. If the sea ice concentration anomalies are entirely absent, the variance of N is even smaller than the experiment with the most sensitive anomalies. Quantifying how the variance of N depends on the presence and sensitivity of sea ice anomalies to N has implications for the simulation of N in global climate models. In the physical system, projected changes in sea ice thickness or extent could alter the sensitivity of B to N, impacting the within-season variability and hence predictability of N.  相似文献   

12.
We performed a modeling study of the cloud processes in a heavy snowfall event occurring in North China on 20–22 December 2004. The nonhydrostatic Mesoscale Model (MM5) was used to carry out experiments with the Reisner-2 explicit microphysical parameterizations in four nested domains to test the sensitivity of simulated heavy snowfall to different snow intercept parameters. Results show that while the different intercept parameters do not significantly affect the accumulated snowfall amounts at the surface in either total amount or location, some microphysical characteristics of the modeled heavy snowfall event are impacted. The budget of cloud microphysics is analyzed to determine the dominant cloud processes. In the control experiment (CTL) with the snow intercept (N os) specified as a function of temperature, the primary simulated hydrometeor is snow, and its mixing ratio is an order of magnitude larger than that of the other cloud species. Relative to CTL, the experiment with a fixed intercept (CON3E6) produced lower snow mixing ratios, more cloud water and graupel mixing ratios. Among the two experiments, while snowfall is slightly smaller in CON3E6, other processes like the rate of graupel fall, condensation and evaporation of cloud water, deposition and sublimation of graupel are all larger in CON3E6 than in CTL. Among CTL, CON3E6, and two more experiments (CON2E7: with a smaller fixed intercept; and NOSQS: N os a function of snow mass mixing ratio), the budget shows that CON3E6 produces the smallest deposition and sublimation of snow, the largest deposition of cloud ice, and the largest conversion from cloud ice to snow.  相似文献   

13.
Summary Climatic changes of summer temperature and precipitation in the greater Alpine region are assessed by using statistical-dynamical downscaling. The downscaling procedure is applied to two 30-year periods (1971–2000 and 2071–2100, summer months only) taken from the results of a transient coupled ocean/atmosphere climate scenario simulation with increasing greenhouse gas concentrations. The downscaling results for the present-day climate are compared with observations. The estimated regional climate change during the next 100 years shows a general warming. The mean summer temperatures increase by 3 to 5 Kelvin. The most intense climatic warming is predicted in the western parts of the Alps. The amount of summer precipitation decreases in most parts of central Europe by more than 20 percent. Increasing precipitation is simulated only over the Adriatic area and parts of eastern central Europe. The results are compared with observed climate trends for the last decades and results of other regional climate change estimations. The observed trends and the majority of the simulated trends (including ours) have a number of common features. However, there are also climate change estimates of other groups which completely contradict our results. Received April 8, 1999 Revised November 16, 1999  相似文献   

14.
A pilot scheme uses upper air data from a few extreme hottest days to identify those and other extreme hottest days measured by 3 stations sampling the California Central Valley (CV). Prior work showed that CV extreme heat wave onsets have characteristic large scale patterns in many upper-air variables; those patterns also occur for the hottest days. A pilot scheme uses areas of two upper-air variables with high significance and consistency to forecast extreme surface temperatures. The scheme projects key parts of composite patterns for one or more variables onto daily weather maps of the corresponding variables resulting in a ??circulation index?? for each day. The circulation index measures how similar the pattern on that day is to the composite patterns in areas dynamically relevant to a CV extremely hot day, with a larger value for a stronger match and larger amplitude. The scheme is tested on the development period (1979?C1988) and on the subsequent 18?year ??independent?? period (1989?C2006). The pilot scheme captures about half of the rare events in the development period, with similar skill for the independent period. Based only on 16?days of extreme heat in the first 10?years, the scheme is not intended to represent the general distribution; however the circulation index has similar kurtosis, variance, and skewness as the observed maximum temperatures. Properties of the high end tail of the distribution are notably improved by adding the second predictor. The scheme outperforms simply using 850?hPa temperature above the CV.  相似文献   

15.
Identifying historical patterns of fluctuation in climate change skepticism guides researchers, policy makers, and science communicators in efforts to catalyze change in the future. We analyzed data from 25 nationally representative polls collected in Australia from 2009 to 2019 (N = 20,655). Although it remains concerningly high, climate skepticism trended down in that 10-year period, particularly among conservatives. Multilevel analyses identified two variables that stood out as being relevant in explaining that trajectory. First, climate change skepticism was positively associated with support for conservative political parties in national polls. Second, climate change skepticism was negatively associated with the annual global temperatures the previous year. There was little evidence that climate change beliefs were associated with economic variables or with seasonal variations in temperature. Furthermore, there was only weak evidence that climate change beliefs were associated with national temperatures. This suggests that global temperatures in the previous year are impactful because of their informational value (as a communication heuristic for the urgency and immediacy of climate change) more so than for their experiential value (in the sense of people actually experiencing warmer weather). Importantly, the effect of previous global temperature was particularly pronounced among those with the strongest levels of skepticism: political conservatives. This suggests that rising global annual temperatures have the power to update beliefs among those most in need of converting to the climate cause.  相似文献   

16.
 The climate during the Last Glacial Maximum (LGM) has been simulated using the UK Universities Global Atmospheric Modelling Programme (UGAMP) general circulation model (GCM) with both prescribed sea surface temperatures (SSTs) based on the CLIMAP reconstruction and computed SSTs with a simple thermodynamic slab ocean. Consistent with the Paleoclimate Modelling Intercomparison Project (PMIP), the other boundary conditions include the large changes in ice-sheet topography and geography, a lower sea level, a lower concentration of CO2 in the atmosphere, and a slightly different insolation pattern at the top of the atmosphere. The results are analysed in terms of changes in atmospheric circulation. Emphasis is given to the changes in surface temperatures, planetary waves, storm tracks and the associated changes in distribution of precipitation. The model responds in a similar manner to the changes in boundary conditions to previous studies in global mean statistics, but differs in its treatment of regional climates. Results also suggest that both the land ice sheets and sea ice introduce significant changes in planetary waves and transient eddy activity, which in turn affect regional climates. The computed SST simulations predict less sea ice and cooler tropical temperatures than those based on CLIMAP SSTs. It is unclear as to whether this is a model and/or a data problem, but the resulting changes in land temperatures and precipitation can be large. Snow mass budget analysis suggests that there is net ice loss along the southern edges of the Laurentide and Fennoscandian ice sheets and net ice gain over other parts of the two ice sheets. The net accumulation is mainly due to the decrease in ablation in the cold climate rather than to the changes in snowfall. The characteristics of the Greenland ice-sheet mass balance in the LGM simulations is also quite different from those in the present-day (PD) simulations. The ablation in the LGM simulations is negligible while it is a very important process in the ice mass budget in the PD simulations. Received: 10 January 1997 / Accepted: 11 December 1997  相似文献   

17.
This study presents a methodology for modeling and mapping the seasonal and annual air temperature and precipitation climate normals over Greece using several topographical and geographical parameters. Data series of air temperature and precipitation from 84 weather stations distributed evenly over Greece are used along with a set of topographical and geographical parameters extracted with Geographic Information System methods from a digital elevation model (DEM). Normalized difference vegetation index (NDVI) obtained from MODIS Aqua satellite data is also used as a geographical parameter. First, the relation of the two climate elements to the topographical and geographical parameters was investigated based on the Pearson’s correlation coefficient to identify the parameters that mostly affect the spatial variability of air temperature and precipitation over Greece. Then a backward stepwise multiple regression was applied to add topographical and geographical parameters as independent variables into a regression equation and develop linear estimation models for both climate parameters. These models are subjected to residual correction using different local interpolation methods, in an attempt to refine the estimated values. The validity of these models is checked through cross-validation error statistics against an independent test subset of station data. The topographical and geographical parameters used as independent variables in the multiple regression models are mostly those found to be strongly correlated with both climatic variables. Models perform best for annual and spring temperatures and effectively for winter and autumn temperatures. Summer temperature spatial variability is rather poorly simulated by the multiple regression model. On the contrary, best performance is obtained for summer and autumn precipitation while the multiple regression model is not able to simulate effectively the spatial distribution of spring precipitation. Results revealed also a relatively weaker model performance for precipitation than that for air temperature probably due to the highly variable nature of precipitation compared to the relatively low spatial variability of air temperature field. The correction of the developed regression models using residuals improved though not significantly the interpolation accuracy.  相似文献   

18.
DNDC, a rainfall-driven and process-oriented model of soil carbon and nitrogen biogeochemistry, is applied to simulate the nitrous oxide emissions from agricultural ecosystem in Southeast China. We simulated the soil N2O emission during a whole rice-wheat rotation cycle (from Nov. 1, 1996 to Oct. 31, 1997) under three different conditions, which are A) no fertilizer, B) both chemical fertilizer and manure and, C) chemical fertilizer only. The processes of N2O emission were discussed in detail by comparing the model outputs with the results from field measurement. The comparison shows that the model is good at simulating most of the N2O emission pulses and trends. Although the simulated N2O emission fluxes are generally less than the measured ones, the model outputs during the dryland period, especially during the wheat reviving and maturing stages in spring, are much better than those during the paddy field period. Some sensitive experiments were made by simulating the N2O emissions in spring, when there is a smallest gap between the simulated fluxes and the measured ones. Meanwhile, the effects of some important regulating factors, such as the rainfall, N deposition by rainfall, temperature, tillage, nitrogen fertilizer and manure application on N2O emission during this period were analyzed. From the analysis, we draw a conclusion that soil moisture and fertilization are the most important regulating factors while the N2O emission is sensitive to some other factors, such as temperature, manure, tillage and the wet deposition of atmospheric nitrate.  相似文献   

19.
The authors examine extreme summer temperatures over East China during 1984-2004 using a regional climate model named CREM(the Climate version of Regional Eta-coordinate Model),which was developed by LASG/IAP.The results show that the main features of the extreme summer temperatures over East China are reproduced well by CREM,and the skill for the minimum temperature is higher than that for the maximum temperature,especially along the Yangtze-Huai River Valley(YHV).The simulated extreme temperatures are lower than those of observation,especially for the maximum temperature.The bias of extreme temperatures is consistent with the cold bias of the climatological mean summer surface air temperature.The skill of the model in simulating the interannual variability of extreme temperatures increases from north to south.The simulated interannual variation of the minimum temperature is more reasonable than the maximum temperature.The underestimation of net solar radiation at the surface leads to a cold bias of the climatological mean temperature.Furthermore,the model underestimates the light and moderate rain,while overestimates heavy rain.It causes the simulated minimum temperature more reasonable than the maximum temperature.  相似文献   

20.
Historical documentary sources, reflecting different port activities in Stockholm, are utilised to derive a 500-year winter/spring temperature reconstruction for the region. These documentary sources reflect sea ice conditions in the harbour inlet and those series that overlap with the instrumental data correlate well with winter/spring temperatures. By refining dendroclimatological methods, the time-series were composited to a mean series and calibrated (1756–1841; r 2?=?66%) against Stockholm January–April temperatures. Strong verification was confirmed (1842–1892; r 2?=?60%; RE/CE?=?0.55). By including the instrumental data, the quantified (QUAN) reconstruction indicates that recent two decades have been the warmest period for the last 500 years. Coldest conditions occurred during the 16th/17th and early 19th centuries. An independent qualitative (QUAL) historical index was also derived for the Stockholm region. Comparison between QUAN and QUAL shows good coherence at inter-annual time-scales, but QUAL distinctly appears to lack low frequency information. Comparison is also made to other winter temperature based annually resolved records for the Baltic region. Between proxy coherence is generally good although it decreases going back in time with the 1500–1550 period being the weakest period—possibly reflecting data quality issues in the different reconstructions.  相似文献   

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