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Indicators of Antarctic ozone depletion
G. E. Bodeker, H. Shiona,H. Eskes
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2005,
Abstract: An assimilated data base of total column ozone measurements from satellites has been used to generate a set of indicators describing attributes of the Antarctic ozone hole for the period 1979 to 2003, including (i) daily measures of the area over Antarctica where ozone levels are below 150 DU, below 220 DU, more than 30% below 1979 to 1981 norms, and more than 50% below 1979 to 1981 norms, (ii) the date of disappearance of 150 DU ozone values, 220 DU ozone values, values 30% below 1979 to 1981 norms, and values 50% below 1979 to 1981 norms, for each year, (iii) daily minimum total column ozone values over Antarctica, and (iv) daily values of the ozone mass deficit based on a O3<220 DU threshold. The assimilated data base combines satellite-based ozone measurements from 4 Total Ozone Mapping Spectrometer (TOMS) instruments, 3 different retrievals from the Global Ozone Monitoring Experiment (GOME), and data from 4 Solar Backscatter Ultra-Violet (SBUV) instruments. Comparisons with the global ground-based Dobson spectrophotometer network are used to remove offsets and drifts between the different data sets to produce a global homogeneous data set that combines the advantages of good spatial coverage of satellite data with good long-term stability of ground-based measurements. One potential use of the derived indices is detection of the expected recovery of the Antarctic ozone hole. The suitability of the derived indicators to this task is discussed in the context of their variability and their susceptibility to saturation effects which makes them less responsive to decreasing stratospheric halogen loading. It is also shown that if the corrections required to match recent Earth Probe TOMS measurements to Dobson measurements are not applied, some of the indictors are affected so as to obscure detection of the recovery of the Antarctic ozone hole.
Indicators of Antarctic ozone depletion  [PDF]
G. E. Bodeker,H. Shiona,H. Eskes
Atmospheric Chemistry and Physics Discussions , 2005,
Abstract: An assimilated data base of total column ozone measurements from satellites has been used to generate a set of indicators describing attributes of the Antarctic ozone hole for the period 1979 to 2003, including (i) daily measures of the area over Antarctica where ozone levels are below 150DU, below 220DU, more than 30% below 1979 to 1981 norms, and more than 50% below 1979 to 1981 norms, (ii) the date of disappearance of 150DU ozone values, 220DU ozone values, values 30% below 1979 to 1981 norms, and values 50% below 1979 to 1981 norms, for each year, (iii) daily minimum total column ozone values over Antarctica, and (iv) daily values of the ozone mass deficit based on a O3<220DU threshold. The assimilated data base combines satellite-based ozone measurements from 4 Total Ozone Mapping Spectrometer (TOMS) instruments, 3 different retrievals from the Global Ozone Monitoring Experiment (GOME), and data from 4 Solar Backscatter Ultra-Violet (SBUV) instruments. Comparisons with the global ground-based Dobson spectrophotometer network are used to remove offsets and drifts between the different data sets to produce a global homogeneous data set that combines the advantages of good spatial coverage of satellite data with good long-term stability of ground-based measurements. One potential use of the derived indices is detection of the expected recovery of the Antarctic ozone hole. The suitability of the derived indicators to this task is discussed in the context of their variability and their susceptibility to saturation effects which makes them less responsive to decreasing stratospheric halogen loading. It is also shown that if the corrections required to match recent Earth Probe TOMS measurements to Dobson measurements are not applied, some of the indictors are affected so as to obscure detection of the recovery of the Antarctic ozone hole.
Detection and attribution of Antarctic climate change
Bracegirdle,Thomas J;
Anales del Instituto de la Patagonia , 2012, DOI: 10.4067/S0718-686X2012000100005
Abstract: the current understanding of climate changes that have occurred in the last 50 years over antarctica is presented with a focus on: (i) a summer warming of the eastern antarctic peninsula, which caused the collapse of the larsen b ice shelf, (ii) the observed significant increase of total sea ice extent and (iii) an anthropogenic ‘fingerprint’ in the antarctic-wide temperature change pattern. the implications of this for predictions of the future are discussed.
Spatial / Temporal Features of Antarctic Climate Change
Ge Ling,Liang Jiaxing,Chen Yiliang,
Ge Ling
,Liang Jiaxing,Chen Yiliang

大气科学进展 , 1996,
Abstract: Based on January 1962-October 1993 mean value series of monthly mean temperature anomalies of 16 Antarctic stations on 10 standard isobaric surfaces from the surface to the 30 hPa, long term trends and periodic features of climate changes from the troposphere to the lower stratosphere over the Antarctic region are investigated by maxi-mum entropy power spectrum analysis, and the relation between climate change of the stratosphere (troposphere) and total ozone (southern 500 hPa circulation) is discussed.
Climate Change Influences on Antarctic Bird Populations
Ma gorzata Korczak-Abshire
Papers on Global Change IGBP , 2010, DOI: 10.2478/v10190-010-0005-3
Abstract: Rapid changes in the major environmental variables like: temperature, wind and precipitation have occurred in the Antarctic region during the last 50 years. In this very sensitive region, even small changes can potentially lead to major environmental perturbations. Then the climate change poses a new challenge to the survival of Antarctic wildlife. As important bioindicators of changes in the ecosystem seabirds and their response to the climate perturbations have been recorded. Atmospheric warming and consequent changes in sea ice conditions have been hypothesized to differentially affect predator populations due to different predator life-history strategies and substantially altered krill recruitment dynamics.
Species composition and abundance of rotifers in different environments of the floodplain of the upper Paraná river, Brazil
Garcia, Aparecida Paula Perez;Lansac-T?ha, Fábio Amodêo;Bonecker, Cláudia Costa;
Revista Brasileira de Zoologia , 1998, DOI: 10.1590/S0101-81751998000200006
Abstract: the purpose of this study was to describe the composition and abundance of rotifers in different environments: one lotie (the ivinheima river) and another lentic (the patos lake) located in the floodplain of the upper paraná river. the influence of limnological variables on the structure and dynamics of rotifers was also examined. samples were taken monthly from march 1992 through february 1993, in the open water region of the lake and river and in the channel between them and, in the littoral region of the lake and river. of the 96 species identified, the best represented families were: brachionidae (20 species), lecanidae (18 species), and trichocercidae (15 species). 55 species were widely distributed, 13 were pantropical, 16 neotropical (8 endemic to south america). trichocerca gracilis was a new record for this floodplain. dipleuchlanis propatula propatula, lecane curvicornis, l. leontina, l. bulla, plationus patulus patulus, platyias quadricornis quadricornis, testudinella patina, and t. mucronata hauriensis were consistently present. more species were recorded during the high water period, probably because of the interconnection among the different environments of the floodplain that allows fauna exchange and an increase in available habitats. rotifer densities were higher mainly in the lake, during the high water. using principal components analysis, was identified four variables that influence the seasonal variation in the rotifer densities: water level, dissolved oxygen, chlorophyll-a concentration, and water temperature.
Climate indicators for Italy: calculation and dissemination
F. Desiato, G. Fioravanti, P. Fraschetti, W. Perconti,A. Toreti
Advances in Science and Research (ASR) , 2011, DOI: 10.5194/asr-6-147-2011
Abstract: In Italy, meteorological data necessary and useful for climate studies are collected, processed and archived by a wide range of national and regional institutions. As a result, the density of the stations, the length and frequency of the observations, the quality control procedures and the database structure vary from one dataset to another. In order to maximize the use of those data for climate knowledge and climate change assessments, a computerized system for the collection, quality control, calculation, regular update and rapid dissemination of climate indicators was developed. The products publicly available through a dedicated web site are described, as well as an example of climate trends estimates over Italy, based on the application of statistical models on climate indicators from quality-checked and homogenised time series.
Climate Change and Trophic Response of the Antarctic Bottom Fauna  [PDF]
Richard B. Aronson, Ryan M. Moody, Linda C. Ivany, Daniel B. Blake, John E. Werner, Alexander Glass
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0004385
Abstract: Background As Earth warms, temperate and subpolar marine species will increasingly shift their geographic ranges poleward. The endemic shelf fauna of Antarctica is especially vulnerable to climate-mediated biological invasions because cold temperatures currently exclude the durophagous (shell-breaking) predators that structure shallow-benthic communities elsewhere. Methodology/Principal Findings We used the Eocene fossil record from Seymour Island, Antarctic Peninsula, to project specifically how global warming will reorganize the nearshore benthos of Antarctica. A long-term cooling trend, which began with a sharp temperature drop ~41 Ma (million years ago), eliminated durophagous predators—teleosts (modern bony fish), decapod crustaceans (crabs and lobsters) and almost all neoselachian elasmobranchs (modern sharks and rays)—from Antarctic nearshore waters after the Eocene. Even prior to those extinctions, durophagous predators became less active as coastal sea temperatures declined from 41 Ma to the end of the Eocene, ~33.5 Ma. In response, dense populations of suspension-feeding ophiuroids and crinoids abruptly appeared. Dense aggregations of brachiopods transcended the cooling event with no apparent change in predation pressure, nor were there changes in the frequency of shell-drilling predation on venerid bivalves. Conclusions/Significance Rapid warming in the Southern Ocean is now removing the physiological barriers to shell-breaking predators, and crabs are returning to the Antarctic Peninsula. Over the coming decades to centuries, we predict a rapid reversal of the Eocene trends. Increasing predation will reduce or eliminate extant dense populations of suspension-feeding echinoderms from nearshore habitats along the Peninsula while brachiopods will continue to form large populations, and the intensity of shell-drilling predation on infaunal bivalves will not change appreciably. In time the ecological effects of global warming could spread to other portions of the Antarctic coast. The differential responses of faunal components will reduce the endemic character of Antarctic subtidal communities, homogenizing them with nearshore communities at lower latitudes.
Prospects for surviving climate change in Antarctic aquatic species
Lloyd S Peck
Frontiers in Zoology , 2005, DOI: 10.1186/1742-9994-2-9
Abstract: In contrast the marine Antarctic environment has very stable temperatures. However, seasonality is intense with very short summers and long winter periods of low to no algal productivity. Marine animals grow slowly, have long generation times, low metabolic rates and low levels of activity. They also die at temperatures between +5°C and +10°C. Failure of oxygen supply mechanisms and loss of aerobic scope defines upper temperature limits. As temperature rises, their ability to perform work declines rapidly before lethal limits are reached, such that 50% of populations of clams and limpets cannot perform essential activities at 2–3°C, and all scallops are incapable of swimming at 2°C. Currently there is little evidence of temperature change in Antarctic marine sites. Models predict average global sea temperatures will rise by around 2°C by 2100. Such a rise would take many Antarctic marine animals beyond their survival limits. Animals have 3 mechanisms for coping with change: they can 1) use physiological flexibility, 2) evolve new adaptations, 3) migrate to better sites. Antarctic marine species have poor physiological scopes, long generation times and live on a continent whose coastline covers fewer degrees of latitude than all others. On all 3 counts Antarctic marine species have poorer prospects than most large faunal groups elsewhere.A current major focus for science is the prospect of global climate change. It is now internationally accepted that we are in a period of global change, that for some measures such as atmospheric carbon dioxide content, is faster than at any time in recent geological history [1,2]. Much effort has been put into producing models of predicted change [1,3,4], and identifying the evidence for change. These models and their outputs have had profound effects on the science conducted and the focus of research in both physical and biological disciplines.Environmental change poses a range of problems for species that vary between site and spe
Responses of Antarctic Tundra Ecosystem to Climate Change and Human Activity
Maria Olech
Papers on Global Change IGBP , 2010, DOI: 10.2478/v10190-010-0004-4
Abstract: Over the last couple of years the Antarctic Peninsula region has been one of the fastest warming regions on the Earth. Rapidly proceeding deglaciation uncovers new areas for colonisation and formation of Antarctic tundra communities. The most evident dynamics, i.e. changes in both biodiversity and structure of tundra communities, are observed in the forefields of retreating glaciers. This paper presents examples of changes in biodiversity and in the direction and rate of succession changes taking place due to climate warming compounded by synanthropization in the maritime Antarctic.
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