Effects of the 2003 European heatwave on the benthic community of a severe transitional ecosystem (Comacchio Saltworks, Italy)

The summer of 2003 was the warmest summer in Europe since the 16th century. Its consequences on the fauna of a transitional ecosystem were studied through biodiversity, functional and ecological indicators, from summer 2002 to winter 2005. The heatwave caused considerable changes in the benthic community structure and relative composition, persisting in 2005. Animal assemblages switched from mollusc- to annelida-dominated. Biodiversity and functional indicators captured changes in community structure and composition, proving to be powerful tools to detect responses related to global warming. Ecological indicators rendered a monotonic response oscillating between bad and poor ecological status across the study period. The resilience of mollusc biocoenosis resulted limited with respect to other taxa, posing concerns about their conservation if, as predicted, the frequency of summers as hot as that of 2003 will progressively increase to become the norm at the end of this century.     

根据树木年轮长记录推测古气候

研究气候变化不能光依靠气象要素的观测记录,因为气象记录年代很短,并且不能充分地描述自然气候状况的变化范围。本文试图利用千年树轮宽度变化的古气候信息,例如用美国西部的刺毛果松树(bristlecone pine)的资料,来推测古气候的状况。由于刺毛果松树个别树木的树龄很高,而且还有一些死亡树木至今仍然存在,所以通过交叉定年代(cross dating),就可以得到很长的树轮宽度年表。所谓交叉定年代是指各树轮序列间宽年轮和窄     

气象学方面的厄尼诺

1.引言对于大多数年份来说,秘鲁和厄瓜多尔海岸以外的海洋表面水是冷的。每年圣诞节前后,一股暖流在厄瓜多尔海岸以南流动,来替换冷的表面水,这种现象被称为厄尼诺。捕鱼受到轻微的影响,但这种影响是短暂的。然而,有些年份(1891、1925、1941、1957—1958、1965、1972—1973和1976)厄尼诺强而且长。沿秘鲁海岸和赤道东太平洋洋面温度上升,并且可以持续一年以上。鳀鱼捕捞遭受破坏,南美西部热带地区发生异常的大雨。在最近几年中,厄尼诺的最初含意已经失去。对于海洋学家和气象学家来说,现在的厄尼诺则意味着这种主要现象。较早的沿南美海岸的海水上翻速度控制着厄尼诺的海洋学理论,已被Wyrtki(1973,1975)有力地反驳了,他假定厄尼诺是由信风强度的振荡造成的。     

The main issues affecting coasts of the Indian and western Pacific Oceans: a meta-analysis from Seas at the Millennium

A review of the world oceans in three volumes by 365 scientists, provides scope for several ‘meta-analyses' of the main problems affecting over 100 areas in the year 2000. This article summarises the main issues affecting a sub-set of the reviewed areas, covering Asian, African and Arabian countries dealt with in Volume 2, which included over 50 articles. From all issues raised, assessment is made of the nature of the major ones, including evaluation of reasons why so many of them remain important issues after so much attention to them. These include long standing problems, several problems more newly flagged as becoming particularly important, the issue of global warming and no less than three related issues connected with fishing and over exploitation. One or two issues such as industrial pollution and sewage, previously considered of almost universal concern, almost traditional pollution issues even, continue to feature strongly for some countries, but while these were almost always referred to in Seas chapters, by and large these categories appear not to be the most pressing of issues today, except in localized areas (albeit areas where huge numbers of people live). Perhaps other issues have simply taken over. They are excluded from this article.     

还我分析！

我们这一代的预报员和气象员认为搞分析是理所当然的事。我们已忘记了,在刚参加工作时由于工作不合要求曾经是如何地苦恼,也忘记了只是在辛苦地分析了几百张图之后才达到了技术合格的要求。我们从来没有有意识地想过“分析”这个技术包括哪些内容和怎样才能保持这一技术。我们考虑这是因为我和我的同事们都已经掌握它了,所以既不感到它特别可贵,也不觉得它特别困难,尽管我记得有一次我曾因一位卓越的高空大气物理学家竟不懂简单的平流层臭氧观测方法而困惑不解。自1960年天气卫星问世以来,它提供前所未有的观测纪录给分析员带来了极好的机会,能把分析技巧运用于这个奇妙的新要素场,可以大大提高分析水     

上空有云流流出的台风的强度变化

一、导言 Erickson 和 Winston,(1972)第一次从气象卫星云图上观测到从西北太平洋的一个命名热带气旋(以下不管其强度,一概称为台风)的中心偶尔有范围很大的一股含有中云和高云的云流向东北方流出。作者们指出,这种云流是由大量的热带的热量和水汽输送到西风带里去造成的。Ramage(1974)研究了中国南海1970年10月的3个台风,得到的结论是:高空云流外流是由于在对流层上层有西风槽逼近而在槽前又有热通量的辐散所引起的。他还发现,在槽线以东的涡度平流会增强台风上空的质量辐散,而在云流形成时,风速也随之加大。他的这个发现与Riehl(1972)的结论是一致的,     

Mesoscale Vortex Generation and Merging Process： A Case Study Associated with a Post-Landfall Tropical Depression

An observational analysis of satellite blackbody temperature (TBB) data and radar images suggests that the mesoscale vortex generation and merging process appeared to be essential for a tropical-depression-related heavy rain event in Shanghai, China. A numerical simulation reproduced the observed mesoscale vortex generation and merging process and the corresponding rain pattern, and then the model outputs were used to study the related dynamics through diagnosing the potential vorticity (PV) equation. The t...     

Ozone during stratospheric warmings at Uccle

The day-to-day variations in ozone content at Uccle (51oN) during some stratospheric warming events are ex-amined. In particular, the attention is focused on the timing of commencement of ozone enhancement prior to peak day of warming and on the relationship in the ozone content between the upper and lower stratosphere. These two features are compared with the predictions of ozone transport models. There seems to be an agreement between mod-el predictions and observed features in some cases.     

SATMOD:综合卫星云图和模式输出参数的一种交互式方法

SATMOD 是一种综合卫星云图和若干模式输出参数的交互式方法。奥地利维也纳气象与地球动力学中央研究所使用这一方法进行卫星-天气学研究、业务分析和预报服务。在本文中,集中用一种重要的天气学现象(急流)来说明 SATMOD 方法。     

PAHs distribution in sediments associated with gas hydrate and oil seepage from the Gulf of Mexico

Six sediment samples collected from the Gulf of Mexico were analyzed. Total concentrations of the PAHs ranged from 52 to 403 ng g⁻¹ dry weight. The lowest PAH concentration without 5–6 rings PAHs appeared in S-1 sample associated with gas hydrate or gas venting. Moreover, S-1 sample had the lowest organic carbon content with 0.85% and highest reduced sulfur level with 1.21% relative to other samples. And, analysis of the sources of PAHs in S-1 sample indicated that both pyrogenic and petrogenic sources, converserly, while S-8, S-10 and S-11 sample suggested petrogenic origin. The distribution of dibenzothiophene, fluorine and dibenzofuran and the maturity parameters of triaromatic steranes suggested that organic matters in S-1 sample were different from that in S-8, S-10 and S-11 sample. This study suggested that organic geochemical data could help in distinguish the characteristic of sediment associated with gas hydrate or with oil seepage.