A global climatology of extreme rainfall rates in the inner core of intense tropical cyclones

The localized rain rate maxima (R_M) of the inner core region of intense tropical cyclones (TCs) are investigated using Version 6 of the Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis data-set from 1998 to 2010. Specifically, this study examines the probabilities of R_M exceeding 25 mm h^?1 (P25) in intense TCs. The 25 mm h^?1 R_M is the 90th percentile of all R_M observations during the study period. The descending order of P25 observed from intense TCs for the six major ocean basins is: the North Indian Ocean, the Atlantic Ocean, the Northwest Pacific Ocean, the South Pacific Ocean, the South Indian Ocean, and the East-central Pacific Ocean. The six major basins have been subdivided into 29 sub-basins to discern regional variability of R_M. P25 increases with increasing TC category in all major basins, except for the South Pacific. Sub-basins with intense TCs that produce extreme rainfall rate maxima include the Bay of Bengal, the South Philippine Sea, the East China Sea, the north coast of Australia, southeast Melanesia, and the Northwest Atlantic. Sub-basins with a higher proportion of category 5 (CAT5) observations than category 3 (CAT3) observations tend to have a greater P25 beyond 60 km from the storm center.     

2008年的湛江土壤湿度特征

对湛江地面气象观测站2008年0～50 cm土壤湿度、降水及蒸发皿蒸发资料进行了分析。结果表明,湛江土壤湿度的垂直分布形态为垂直均匀型;按土壤湿度随时间的变化规律,可将其划分为春季相对稳定期、夏季增墒期和秋季迅速下降期3个时段。对0～10 cm、10～30 cm与30～50 cm土层土壤湿度进行回归分析,表明土壤湿度与降水量、蒸发皿蒸发量存在线性关系,除春季30～50 cm土壤湿度的预报值明显偏低外,其余回归方程的预报结果均较好。同一土壤类型、不同时段,或同一时段、不同的土壤层次,拟合的方程不同,反映出土壤湿度时间和空间分布的复杂性。     

广州市低温日的气候特点及其变化

统计了1951～2008年广州市最低气温≤5℃的低温日数,发现近58年来呈现年低温日数减少、低温终日提前、低温期缩短的趋势,年低温日数主要有2～3年和7～8年的变化周期.对低温日数异常年景冬季500 hPa环流进行合成分析发现,广州年低温日数显著偏多和偏少年份的亚欧地区冬季500 hPa高度距平场基本呈反位相分布.另外...     

基于MOM4模式的太平洋区域环流模式的模拟评估与分析

本文初步评估基于MOM4海洋环流模式建立的较高分辨率(0.25(°)×0.25(°))太平洋区域环流模式的模拟能力。研究表明,模式较好的再现了气候态的海表面温度、盐度、流、海表高度、等密面位涡模态、混合层深度等水平分布场;同时也较为准确地模拟了黑潮流轴的流量,温盐流结构等。相对于低分辨率模式,具有高分辨率的模式能有效地控制黑潮的流幅,以及黑潮离岸的位置,并且对模态水的模拟也比较清晰。     

A 38-Year Climatology of Explosive Cyclones over the Northern Hemisphere

Explosive cyclones(ECs)over two basins in the Northern Hemisphere(20°-90°N)from January 1979 to December2016 are investigated using ERA-Interim and Optimum Interpolation Sea Surface Temperature(OISST)data.The classical definition of an EC is modified considering not only the rapid drop of the central sea level pressure of the cyclone,but also the strong wind speed at the height of 10 m in which maximum wind speeds greater than 17.2 m s^-1are included.According to the locations of the northern Atlantic and northern Pacific,the whole Northern Hemisphere is divided into the"A region"(20°-90°N,90°W-90°E)and"P region"(20°-90°N,90°E-90°W).Over both the A and P regions,the climatological features of ECs,such as their spatial distribution,intensity,seasonal variation,interannual variation,and moving tracks,are documented.     

金苞花组培苗安全养护的气候环境条件

本文以金苞花为例,尝试了组培苗从试管内到自然条件下安全养护的小气候环境模拟并获得成功,提出了“关键阶段,过渡阶段和适应阶段”的三段安全养护措施及其相应的气象条件。这对名贵花卉的商业性生产是有意义的。     

URBAN HEAT ISLAND AND URBAN HEALTH: EARLY AMERICAN PERSPECTIVES*

The nature and sources of early American understanding of an important form of human-induced climatic change, the urban heat island effect, are considered. Recognition and explanation of the phenomenon occured both earlier and more widely than is usually supposed. Interest stemmed not only from concerns that remain significant today, but from others that have been discarded, notably anticontagionist theories of the causation of disease.     

成都城市发展对气候影响的初步探讨

本文通过成都城市发展前后气候要素变化的对比分析,探索了城市化对成都市气候影响的基本规律,并用统计方法得出了城市“热岛”强度(△T,△Tmin)与城市人口总户数及建成区面积密切相关的客观事实,为改善和治理成都城市气候提供了一定的依据。     

A NEW CHALLENGE FOR CLIMATE STUDIES IN GEOGRAPHY

Greater emphasis is being placed on large-scale (synoptic and dynamic) climatology in geography. Concurrently, climatological research as a whole has evolved to view climate as a complex, integrated and interactive global system. In this context, we review new directions in large-scale climate studies in geography. We conclude that no matter at which climatic scale geographers are working, the new challenge is to integrate their research and teaching activities into a more holistic, global-systems approach while maintaining and improving their traditional strengths.     

HEATING DEGREE DAY RESEARCH IN ALBERTA: RESIDENTS CONSERVE NATURAL GAS

A high correlation exists between monthly population-weighted heating degree days (below 18C) and the use of natural gas per household for residential heating in Alberta for the period 1962–80. The use of natural gas for residential heating per household declines since 1973 following a sharp increase in gas prices.