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991.
Qin Jin Bai Hongying Su Kai Liu Rongjuan Zhai Danping Wang Jun Li Shuheng Zhou Qi Li Bin 《Theoretical and Applied Climatology》2018,133(1-2):633-645
Theoretical and Applied Climatology - Previous dendroclimatical studies have been based on the relationship between tree growth and instrumental climate data recorded at lower land meteorological... 相似文献
992.
该研究模拟了全球各区域2008-2050年的经济发展和碳排放状况,并将该模拟结果设定为基准情景。在基准情景中全球GDP随时间增长,而全球的碳排放同样表现出增长趋势。为了模拟碳税政策的减排效应及其对经济的影响,本文构建了其他3种碳税政策情景。情景1,将碳税收入作为一般性财政收入,此时全球升温减缓,世界碳排放下降显著,但中国、印度、俄罗斯、马来西亚和印度尼西亚等发展中国家经济发展严重受创,世界经济不均衡加剧。情景2,将各区域的碳税收入汇总之后按照比例统一分配,该情景下,世界碳减排规模较情景1略有下降,但世界各区域的经济较基准情景得到更好的发展。情景3,碳税税率随时间阶段性增长,此时,碳税政策对全球升温的控制更显著;世界各区域,尤其是发展中国家(地区),经济增长更迅速。另外,碳税收入用来提升区域技术进步,在一定程度上促进了产业的优化升级。碳税政策与技术进步的协同减排政策,考虑了区域经济发展的不均衡性,兼顾了气候治理的公平性,是一种有效、可行的全球气候治理政策。 相似文献
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994.
In this paper, a nonlinear optimization method is used to explore the finite-time instability of the atmospheric circulation
with a three-level quasigeostrophic model under the framework of the conditional nonlinear optimal perturbation (CNOP). As
a natural generalization of linear singular vector (SV), CNOP is defined as an initial perturbation that makes the cost function
the maximum at a prescribed forecast time under certain physical constraint conditions. Special attentions are paid to the
different structures and energy evolutions of the optimal perturbations. 相似文献
995.
Forced response of the East Asian summer rainfall over the past millennium: results from a coupled model simulation 总被引:1,自引:0,他引:1
The centennial?Cmillennial variation of the East Asian summer monsoon (EASM) precipitation over the past 1000?years was investigated through the analysis of a millennium simulation of the coupled ECHO-G model. The model results indicate that the centennial?Cmillennial variation of the EASM is essentially a forced response to the external radiative forcing (insolation, volcanic aerosol, and green house gases). The strength of the response depends on latitude; and the spatial structure of the centennial?Cmillennial variation differs from the interannual variability that arises primarily from the internal feedback processes within the climate system. On millennial time scale, the extratropical and subtropical precipitation was generally strong during Medieval Warm Period (MWP) and weak during Little Ice Age (LIA). The tropical rainfall is insensitive to the effective solar radiation forcing (insolation plus radiative effect of volcanic aerosols) but significantly responds to the modern anthropogenic radiative forcing. On centennial time scale, the variation of the extratropical and subtropical rainfall also tends to follow the effective solar radiation forcing closely. The forced response features in-phase rainfall variability between the extratropics and subtropics, which is in contrast to the anti-correlation on the interannual time scale. Further, the behavior of the interannual?Cdecadal variation in the extratropics is effectively modulated by change of the mean states on the millennial time scale, suggesting that the structure of the internal mode may vary with significant changes in the external forcing. These findings imply that on the millennial time scale, (a) the proxy data in the extratropical EA may more sensitively reflect the EASM rainfall variations, and (b) the Meiyu and the northern China rainfall provide a consistent measure for the EASM strength. 相似文献
996.
Cailin?Wang Xuehui?RenEmail author Ying?Li 《Theoretical and Applied Climatology》2017,127(1-2):169-185
Rainfall in New South Wales (NSW), located in the southeast of the Australian continent, is known to be influenced by four major climate drivers: the El Niño/Southern Oscillation (ENSO), the Interdecadal Pacific Oscillation (IPO), the Southern Annular Mode (SAM) and the Indian Ocean Dipole (IOD). Many studies have shown the influences of ENSO, IPO modulation, SAM and IOD on rainfall in Australia and on southeast Australia in particular. However, only limited work has been undertaken using a multiple regression framework to examine the extent of the combined effect of these climate drivers on rainfall. This paper analysed the role of these combined climate drivers and their interaction on the rainfall in NSW using Bayesian Model Averaging (BMA) to account for model uncertainty by considering each of the linear models across the whole model space which is equal to the set of all possible combinations of predictors to find the model posterior probabilities and their expected predictor coefficients. Using BMA for linear regression models, we are able to corroborate and confirm the results from many previous studies. In addition, the method gives the ranking order of importance and the probability of the association of each of the climate drivers and their interaction on the rainfall at a site. The ability to quantify the relative contribution of the climate drivers offers the key to understand the complex interaction of drivers on rainfall, or lack of rainfall in a region, such as the three big droughts in southeastern Australia which have been the subject of discussion and debate recently on their causes. 相似文献
997.
June-Yi Lee Bin Wang Q. Ding K.-J. Ha J.-B. Ahn A. Kumar B. Stern O. Alves 《Climate Dynamics》2011,37(5-6):1189-1203
The retrospective forecast skill of three coupled climate models (NCEP CFS, GFDL CM2.1, and CAWCR POAMA 1.5) and their multi-model ensemble (MME) is evaluated, focusing on the Northern Hemisphere (NH) summer upper-tropospheric circulation along with surface temperature and precipitation for the 25-year period of 1981–2005. The seasonal prediction skill for the NH 200-hPa geopotential height basically comes from the coupled models’ ability in predicting the first two empirical orthogonal function (EOF) modes of interannual variability, because the models cannot replicate the residual higher modes. The first two leading EOF modes of the summer 200-hPa circulation account for about 84% (35.4%) of the total variability over the NH tropics (extratropics) and offer a hint of realizable potential predictability. The MME is able to predict both spatial and temporal characteristics of the first EOF mode (EOF1) even at a 5-month lead (January initial condition) with a pattern correlation coefficient (PCC) skill of 0.96 and a temporal correlation coefficient (TCC) skill of 0.62. This long-lead predictability of the EOF1 comes mainly from the prolonged impacts of El Niño-Southern Oscillation (ENSO) as the EOF1 tends to occur during the summer after the mature phase of ENSO. The second EOF mode (EOF2), on the other hand, is related to the developing ENSO and also the interdecadal variability of the sea surface temperature over the North Pacific and North Atlantic Ocean. The MME also captures the EOF2 at a 5-month lead with a PCC skill of 0.87 and a TCC skill of 0.67, but these skills are mainly obtained from the zonally symmetric component of the EOF2, not the prominent wavelike structure, the so-called circumglobal teleconnection (CGT) pattern. In both observation and the 1-month lead MME prediction, the first two leading modes are accompanied by significant rainfall and surface air temperature anomalies in the continental regions of the NH extratropics. The MME’s success in predicting the EOF1 (EOF2) is likely to lead to a better prediction of JJA precipitation anomalies over East Asia and the North Pacific (central and southern Europe and western North America). 相似文献
998.
利用1971—2001年探空资料以及ERA-40和NCEP/NCAR再分析资料分别得到地面到300 hPa我国大陆上空大气柱水汽含量,对3种不同资料所得的柱水汽含量的空间分布特征以及线性趋势进行对比分析。结果表明:3种资料得到的柱水汽含量年平均和季节平均的空间分布特征一致;3种资料年平均的线性变化趋势在东北地区、内蒙古东部地区,西南地区北部、华南沿海和新疆北部地区均呈增加趋势;在华北和华东的部分地区,ERA-40和NCEP/NCAR再分析资料为降低趋势,而探空资料得到的柱水汽含量变化相对较小,但未通过信度检验;探空资料得到的柱水汽含量的相对变化显示我国东北地区、内蒙古东部地区、新疆地区的增加更显著。 相似文献
999.
1000.