The Fourth Assessment Report (AR4) of the Intergovernmental Panel of Climate Change (IPCC) concluded that the climate projection using climate models that took account of both human and natural factors provided credib...The Fourth Assessment Report (AR4) of the Intergovernmental Panel of Climate Change (IPCC) concluded that the climate projection using climate models that took account of both human and natural factors provided credible quantitative estimates of future climate change; however, the mismatches between the IPCC AR4 model ensembles and the observations, especially the multi-decadal variability (MDV), have cast shadows on the confidence of the model-based decadal projections of future cli mate. This paper reports an evaluation of many individual runs of AR4 models in the simulation of past global mean tempera ture. We find that most of the individual model runs fail to reproduce the MDV of past climate, which may have led to the overestimation of the projection of global warming for the next 40 years or so. Based on such an evaluation, we propose an al ternative approach, in which the MDV signal is taken into account, to project the global mean temperature for the next 40 years and obtain that the global warming during 2011–2050 could be much smaller than the AR4 projection.展开更多
In our experiments,the PL spectra of several In x Ga 1 x N alloy samples with In contents x=0.1,0.15 and 0.25 were measured as a function of temperature ranging from 10 K to 300 K.S-shaped temperature dependencies wer...In our experiments,the PL spectra of several In x Ga 1 x N alloy samples with In contents x=0.1,0.15 and 0.25 were measured as a function of temperature ranging from 10 K to 300 K.S-shaped temperature dependencies were observed in all InGaN samples and a sharp decrease in the full width at half maximum occurred with decreasing temperature in the moderate temperature region.It was found that both phenomena are relative to localization effects.In addition,the degree of localization effects in three samples was investigated using the band-tail model.Our findings are presented in this paper.展开更多
基金supported by the National Basic Research Program of Chi-na (Grant No. 2011CB952000)the National Natural Science Founda-tion of China (Grant No. 40810059003)+1 种基金Qian Cheng was partly supported by the "Strategic Priority Research Program" of the Chinese Academy of Sciences (Grant No. XDA05090103)Wu Zhaohua was supported by the Natural Science Foundation of USA (Grant No. ATM-0917743)
文摘The Fourth Assessment Report (AR4) of the Intergovernmental Panel of Climate Change (IPCC) concluded that the climate projection using climate models that took account of both human and natural factors provided credible quantitative estimates of future climate change; however, the mismatches between the IPCC AR4 model ensembles and the observations, especially the multi-decadal variability (MDV), have cast shadows on the confidence of the model-based decadal projections of future cli mate. This paper reports an evaluation of many individual runs of AR4 models in the simulation of past global mean tempera ture. We find that most of the individual model runs fail to reproduce the MDV of past climate, which may have led to the overestimation of the projection of global warming for the next 40 years or so. Based on such an evaluation, we propose an al ternative approach, in which the MDV signal is taken into account, to project the global mean temperature for the next 40 years and obtain that the global warming during 2011–2050 could be much smaller than the AR4 projection.
基金supported by the Special Funds for Major State Basic Research Project (Grant No. 2011CB301901)the National Natural Science Foundation of China (Grant Nos. 60820106003,60990311 and 60906025)+1 种基金the Natural Science Foundation of Jiangsu Province (Grant Nos.BK2008019 and BK2009255)the Research Funds from NJU-Yangzhou Institute of Opto-electronics
文摘In our experiments,the PL spectra of several In x Ga 1 x N alloy samples with In contents x=0.1,0.15 and 0.25 were measured as a function of temperature ranging from 10 K to 300 K.S-shaped temperature dependencies were observed in all InGaN samples and a sharp decrease in the full width at half maximum occurred with decreasing temperature in the moderate temperature region.It was found that both phenomena are relative to localization effects.In addition,the degree of localization effects in three samples was investigated using the band-tail model.Our findings are presented in this paper.
