卫星遥感海南岛气候特性的研究

利用NOAA极轨气象卫星的AVHRR资料,研究了海南岛干、湿两季在无云情况下的下垫面短波反射率、植被指数、下垫面温度和射出长波辐射的分布及变化特征。结果表明利用气象卫星资料可以较详细地了解气候形成的主要因素之一——下垫面状况。     

土壤热异常影响地表能量平衡的个例分析和数值模拟

The statistical relationship between soil thermal anomaly and short-term climate change is presented based on a typical case study. Furthermore, possible physical mechanisms behind the relationship are revealed through using an off-line land surface model with a reasonable soil thermal forcing at the bottom of the soil layer.In the first experiment, the given heat flux is 5 W m-2 at the bottom of the soil layer (in depth of 6.3 m)for 3 months, while only a positive ground temperature anomaly of 0.06℃ can be found compared to the control run. The anomaly, however, could reach 0.65℃ if the soil thermal conductivity was one order of magnitude larger. It could be even as large as 0.81℃ assuming the heat flux at bottom is 10 W m-2. Meanwhile, an increase of about 10 W m-2 was detected both for heat flux in soil and sensible heat on land surface, which is not neglectable to the short-term climate change. The results show that considerable response in land surface energy budget could be expected when the soil thermal forcing reaches a certain spatial-tem poral scale. Therefore, land surface models should not ignore the upward heat flux from the bottom of the soil layer. Moreover, integration for a longer period of time and coupled land-atmosphere model are also necessary for the better understanding of this issue.     

Study on the Evolution of a Northeast China Cold Vortex during the Spring of 2010

Based on the final analysis data with horizontal resolution of 1°× 1°（four times a day） from the National Centers for Environmental Prediction（NCEP）, a typical Northeast China cold vortex（NCCV） during the spring of 2010 was examined with the quasi-Lagrange- form eddy flux circulation（EFC） budget equation. Results indicated that the mechanisms that account for the development, maintenance, and attenuation of the cyclone varied with levels and stages. Displacement of the cyclone and transports by background environmental circulations dominated the variation of the cyclone in the middle and upper levels, whereas displacement and divergence associated with the cyclone dominated the evolution of the NCCV in the middle and lower levels. Moreover, interactions between the NCCV and other subsynoptic weather systems were important for the development of the cyclone, and the pattern of background environmental circulations was also important for the evolution of the NCCV, since the cyclone enhanced（weakened） as it moved from areas of low（high） vorticity to high（low） ones.     

1986年和1987年秋季西太平洋赤道附近海域的辐射状况

本文利用1986和1987年秋季在西太平洋赤道海域取得的短期辐射资料,分析了这一特定海域的辐射状况。揭示了所在海域太阳辐射的一些特征。这对了解该海域海气界面上的热状况以及它对所在海域天气气候的影响无疑都有帮助。     

黄河流域旱涝年地面热量收支变化特征

根据北京、郑州３年热量平衡观测资料,建立波文（Ｂｏｗｅｎ）比计算模式。并用此模式及辐射计算式等估计黄河流域８年５－８月地面月辐射收支、蒸发耗热、湍流热交换量和土壤热交换量,并比较分析旱涝年它们的差异以及随旱涝（用降水距平表示）的变化。     

Temporal and Spatial Scale Dependence of Precipitation Analysis over the Tropical Deep Convective Regime

Data from Goddard cumulus ensemble model experiment are used to study temporal and spatial scale dependence of tropical rainfall separation analysis based on cloud budget during Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment(TOGA COARE).The analysis shows that the calculations of model domain mean or time-mean grid-scale mean simulation data overestimate the rain rates of the two rainfall types associated with net condensation but they severely underestimate the rain rate of the rainfall type associated with net evaporation and hydrometeor convergence.     

黑河地区大气沙尘对地面辐射能收支的影响

利用１９９１年２月下旬至５月中旬ＨＥＩＦＥ张掖绿洲和沙漠站大气浑浊度观测和地面辐射平衡各个分量观测资料,分析和估算了大气沙尘对地面辐射能收支的影响,晴天大气透过率和达地面的短波辐射与大气浑浊度系数有产好的负相关,大气军浊系数增大时透过率和地面总辐射减少,大气浑浊度系数增大０．１,地面总辐射减少１．３％～１．９％,４月大气浑浊度由０．１增大到０．６,正午时刻地面总辐射减少６７．６～８５．８Ｗ／ｍ＾２     

Estimating Global Distribution of Evapotranspiration and Water Balance Using Complementary Methods

ABSTRACT

The authors propose a modified complementary method to estimate regional evapotranspiration (ET) under different climatic and physical conditions using only meteorological data. The purpose of this study is to investigate the applicability of the modified complementary method for estimating global ET distribution and corresponding water balance. Gridded data from the Climate Research Unit, University of East Anglia, with 30 min spatial resolution and monthly time steps are used. Using the Thornthwaite water budget, monthly maps of global water surplus (precipitation minus ET) are produced. The results show good agreement with many previous studies. The average annual precipitation, ET, and water surplus are 690, 434, and 256?mm, respectively. The results show that the modified model can predict regional ET using meteorological data and can be used to assess global water resources. Consequently, the proposed method has strong potential for projecting water resource balance under future climate change.     

Comparative assessment of Japan's long-term carbon budget under different effort-sharing principles

This article assesses Japan's carbon budgets up to 2100 in the global efforts to achieve the 2?°C target under different effort-sharing approaches based on long-term GHG mitigation scenarios published in 13 studies. The article also presents exemplary emission trajectories for Japan to stay within the calculated budget.

The literature data allow for an in-depth analysis of four effort-sharing categories. For a 450?ppm CO₂e stabilization level, the remaining carbon budgets for 2014–2100 were negative for the effort-sharing category that emphasizes historical responsibility and capability. For the other three, including the reference ‘Cost-effectiveness’ category, which showed the highest budget range among all categories, the calculated remaining budgets (20th and 80th percentile ranges) would run out in 21–29 years if the current emission levels were to continue. A 550?ppm CO₂e stabilization level increases the budgets by 6–17 years-equivalent of the current emissions, depending on the effort-sharing category. Exemplary emissions trajectories staying within the calculated budgets were also analysed for ‘Equality’, ‘Staged’ and ‘Cost-effectiveness’ categories. For a 450?ppm CO₂e stabilization level, Japan's GHG emissions would need to phase out sometime between 2045 and 2080, and the emission reductions in 2030 would be at least 16–29% below 1990 levels even for the most lenient ‘Cost-effectiveness’ category, and 29–36% for the ‘Equality’ category. The start year for accelerated emissions reductions and the emissions convergence level in the long term have major impact on the emissions reduction rates that need to be achieved, particularly in the case of smaller budgets.

Policy relevance

In previous climate mitigation target formulation processes for 2020 and 2030 in Japan, neither equity principles nor long-term management of cumulative GHG emissions was at the centre of discussion. This article quantitatively assesses how much more GHGs Japan can emit by 2100 to achieve the 2?°C target in light of different effort-sharing approaches, and how Japan's GHG emissions can be managed up to 2100. The long-term implications of recent energy policy developments following the Fukushima nuclear disaster for the calculated carbon budgets are also discussed.