副热带高压气候动力学研究回顾

基于早期副热带高压气候动力学的研究,本文重点介绍了近10 a在南亚高压和西太平洋副热带高压形成和变异机理方面的动力学研究,包括南亚高压的建立和维持机理、副热带高压的季节变化、年际—年代际变化和未来预估,最后讨论了需要进一步深入研究的方面。

平原湖区农田防护林小气候效应

江汉平原地处湖北省中南部,是本省乃至全国重要的商品粮、棉、油、渔等农副产品生产基地.素有"鱼米之乡"美称的洪湖市,位于江汉平原东南端,万里长江自西向东,横贯境内135公里.全市地势低洼,河流湖泊众多,水面积占全市总面积的23.89%.受副热带季风气候影响,本地地理条件优越,气候资源丰富,所以进行气候资源的综合考察,对本地区经济计划的制定和整体经济的开发,将有极大的作用.

杭州市盛夏期死亡人数的灰色关联分析及其趋势预测

一、引言众所周知,自然环境中的天气气候与人体的健康存在着十分密切的关系。杭州市地处副热带季风气候区,冬寒夏热,干湿分明。因季风的不稳定性造成气象灾害极其频,风寒暑湿燥火‘六淫’易发。这样,一方面会直接影响人体新陈代谢致使体质下降,并在生物性病因及媒介生物的繁殖和传播条件下,诱发疾病并使病情恶化;另一方面。

南卡罗来纳大学：自带“背景乐”的美式校园充满人情味

南卡罗来纳大学(University of SouthCarolina)位于哥伦比亚市的主校区,毗邻阿帕拉契山脉与大西洋沿岸沙滩,副热带气候特征致使这里的夏季漫长而潮湿。顾问团抵达南卡校园当天,便见到一个太阳高挂的晴天。时逢校园内举行“Home coming”(校友返校日),当看到校园广场上色彩鲜艳的手绘宣传和活力奔走的学生时,天气带来的闷热一扫而空,耳旁仿佛响起了“背景乐”—一代人心中代表着的美式校园生活的电影《歌舞青春》的主题曲。

Growth characteristics of multipurpose tree species, crop productivity and soil properties in agroforestry systems under subtropical humid climate in India

Multipurpose tree species （MPTs） were studied in an agroforestry arboretum under subtropical humid climate in Northeast India. Out of 12 MPTs planted under agroforestry systems, Acacia auriculiformis in spacing of 2 m × 2 m （2500 stems·hm^-2） could have the potentiality to meet the timber/fuelwood requirement due to its high wood production of 635 m^3·hm^-2 with mean annual increment （MAI） of 2.54×10^-2 m^3.treel.a^-1 in a short rotation period of 10 years. Thus, A. auriculiformis is a short rotation forest tree species suitable to grow in subtropical humid climate. On the other hand, at 16 years of age, Eucalyptus hybrid and Michelia champaca in spacing of 3 m × 3 m （1111 stems.hm^2） produced appreciably high timber volume of 315 m^3.hm^-2 and 165 m^3.hm^-2 with MAI of 1.77×10^-2 m^3.tree^-1·a^-1 and 0.92×10.2 m^3.tree^-1.a^-1, respectively. At 16 years of age, Gmelina arborea produced a timber volume of 147 m^3.hm^-2 with MAI of 1.47×10^-2 m^3.tree^-1.a^-1 followed by Samania saman （140 m^3.hm^-2）, Albizziaprocera （113 m^3·hm^-2） and Tectona grandis （79 m3.hm^-2） with MAI of 1.40, 1.13 and 0.78 × 10^-2 m^3 .tree^-1a^-1, respectively in 4 m × 4 m spacing （625 stems.hm^-2）. Gliricidia maculata and Leucaena leucocephala could be used as live fences around the farm boundary to supply their N-rich leaves for mulch as well as manure to crops. In agroforestry arboretum, direct seeded upland rice （Oryza sativa - variety, AR-11）, groundnut （Arachis hypogaea - variety, JL-24） and sesamum （Sesamum indicum - variety, B-67） were grown during the initial period upto 8 years of tree establishment. Under other MPTs, there was a reduction in crop productivity as compared to open space. After 8 years of tree establishment, horti-silvi and silvi-pastoral systems were developed and pineapple （Ananas comosus - variety Queen）, turmeric （Curcuma longa -variety RCT -1） and cowpea （Vigna sinensis - variety Pusa Barsati） as forage crop were raised. The productivity of pineapple, turmeric and cowpea was comparatively high under Azadirachta indica. The productivity of horticultural and forage crops in association with trees such as G. arborea, A. procera, S. saman, T. grandis and M. champaca of high timber value could be harnessed as viable agroforestry systems. Changes in soil properties were also monitored. Amelioration of soil acidity, increase in soil organic carbon, and enhanced humification of soil humus, high nutrient availability, low soil erodibility and high surface soil （0-15 cm） moisture availability were noted in soils under MPTs.

Projected changes in the western North Pacific subtropical high under six global warming targets

The summer western North Pacific subtropical high(WNPSH) has large influences on the East Asian summer climate. Many studies have focused on the projected changes in the WNPSH, but little is known about the changes under different global warming targets, such as 1.5℃ and 2.0℃. This study investigates the changes in the WNPSH under six global warming targets(1.5℃, 2.0℃, 2.5℃,3.0℃, 3.5℃, and 4.0℃) in both the mid-and lower troposphere, using the outputs of CMIP5 model in historical simulations and under Representative Concentration Pathway 8.5. The projected changes in the WNPSH, which is measured by multiple variables, show that it changes little under the 1.5℃ target in the mid-troposphere, but weakens and retreats approximately 2.5° in longitude under the 2.0℃ target. It tends to linearly weaken with warming greater than 2.5℃ and shifts eastward by approximately 6.0° in longitude by the 4.0℃ target. Meanwhile, the WNPSH intensifies and extends westward under the 1.5℃ target in the lower troposphere, but changes little with warming rising from 1.5℃ to 2.0℃. It is projected to extend westward by approximately2.0° in longitude by the 4.0℃ target.

Reconstruction of Conceptual Prediction Model for the Three Rainfall Patterns in the summer of eastern China under global warming

With the influence of global warming,the global climate has undergone significant inter-decadal variation since the late 1970s.Although El Nio-Southern Oscillation(ENSO)has been the strongest signal for predicting global climate inter-annual variability,its relation with the summer rainfall in China has significantly changed,and its indicative function on the summer rainfall in China has weakened.This has led to a significant decrease in the accuracy rate of early conceptual prediction models for the Three Rainfall Patterns in the summer of eastern China.On the basis of the difference analysis of atmospheric circulation system configuration in summer,as well as the interaction of ocean and atmospheric in previous winter between two phases,i.e.before and after the significant global warming(1951 to 1978 and 1979 to 2012,respectively),we concluded that(1)Under different inter-decadal backgrounds,the atmospheric circulations that impacted the Three Rainfall Patterns in the summer of eastern China showed consistency,but in the latter phase of the global warming,the Western Pacific Subtropical High(WPSH)was on the strong side,the position of which was in the south,and the blocking high in the Eurasia mid-high latitudes was active,while the polar vortex extended to the south,and meridional circulation intensified.This circulation background may have been conducive to the increase of the circulation frequency of Patterns II and III,and the decrease of the circulation frequency of Pattern I,thus leading to more Patterns II and III and fewer Pattern I in the summer rainfall of eastern China.(2)In the former phase,the corresponding previous winter SST fields of different rainfall patterns showed visible differences.The impact of ENSO on North Pacific Oscillation(NPO)was great,and the identification ability of which on Patterns I and II of summer rainfall was effective.In the latter phase,this identification ability decreased,while the impact of ENSO on the Pacific/North American(PNA)teleconnection pattern increased,and the identification ability of the PNA on Patterns II and III also increased.Based on the new inter-decadal climate background,this study reconstructs the conceptual prediction model for the Three Rainfall Patterns in summer of eastern China by using the previous winter PNA and the Eurasian(EU)teleconnection indexes.The fitting effect was satisfying,though it is necessary to be further tested.