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1.
An existing Ecopath with Ecosim (EwE) model for the Central North Pacific was updated and modified to focus on the area used by the Hawaii-based pelagic longline fishery. The EwE model was combined with output from a coupled NOAA Geophysical Fluid Dynamics Laboratory climate and biogeochemical model to investigate the likely ecosystem impacts of fishing and climate-induced primary productivity changes. Four simulations were conducted based on 2 fishing effort and climate scenarios from 2010 to 2100. Modeled small and large phytoplankton biomass decreased by 10 % and 20 % respectively, resulting in a 10 % decline in the total biomass of all higher trophic level groups combined. Climate impacts also affected the Hawaii longline fishery, with a 25–29 % reduction in modeled target species yield. Climate impacts on the ecosystem and the fishery were partially mitigated by a drop in fishing effort. Scenarios with a 50 % reduction in fishing effort partially restored longline target species yield to current levels, and decreased longline non-target species yield. These model results suggest that a further reduction in fishery landings mortality over time than the 2010 level may be necessary to mitigate climate impacts and help sustain yields of commercially preferred fish species targeted by the Hawaii longline fishery through the 21st century.  相似文献   

2.
Several lines of evidence show that climatic variation and global warming can have a major effect on fisheries production and replenishment. To prevent overfishing and rebuild overfished stocks under changing and uncertain environmental conditions, new research partnerships between fisheries scientists and climate change experts are required. The International Workshop on Climate and Oceanic Fisheries held in Rarotonga, Cook Islands, 3–5 October 2011, brought representatives from these disciplines together to consider the effects of climate variability and change on oceanic fisheries, the tools and strategies required for identifying potential impacts on oceanic fisheries, and the priority adaptations for sustaining future harvests, especially in the Pacific Ocean. Recommendations made by the workshop included (1) development and implementation of sustainable management measures for fisheries; (2) long-term commitment to monitoring necessary to assess stock status and to conduct integrated ecosystem assessments; (3) process oriented research to evaluate the potential of marine species for adaptation to a changing ocean environment; (4) provision of improved national meteorological and hydrological services to fisheries agencies, enterprises and communities; (5) continuing communication of potential impacts and adaptation strategies to stakeholders to reduce the threats to oceanic fisheries and capitalise on opportunities; and (6) continued collaborative efforts between meteorological, oceanographic, biological and fisheries researchers and management agencies to better monitor and understand the impacts of short-term variability and longer-term change on oceanic fisheries.  相似文献   

3.
The four species of tuna that underpin oceanic fisheries in the tropical Pacific (skipjack, yellowfin, bigeye and albacore tuna) deliver great economic and social benefits to Pacific Island countries and territories (PICTs). Domestic tuna fleets and local fish processing operations contribute 3–20 % to gross domestic product in four PICTs and licence fees from foreign fleets provide an average of 3–40 % of government revenue for seven PICTs. More than 12,000 people are employed in tuna processing facilities and on tuna fishing vessels. Fish is a cornerstone of food security for many PICTs and provides 50–90 % of dietary animal protein in rural areas. Several PICTs have plans to (1) increase the benefits they receive from oceanic fisheries by increasing the amount of tuna processed locally, and (2) allocate more tuna for the food security of their rapidly growing populations. The projected effects of climate change on the distribution of tuna in the tropical Pacific Ocean, due to increases in sea surface temperature, changes in velocity of major currents and decreases in nutrient supply to the photic zone from greater stratification, are likely to affect these plans. PICTs in the east of the region with a high dependence on licence fees for government revenue are expected to receive more revenue as tuna catches increase in their exclusive economic zones. On the other hand, countries in the west may encounter problems securing enough fish for their canneries as tuna are redistributed progressively to the east. Changes in the distribution of tuna will also affect the proportions of national tuna catches required for food security. We present priority adaptations to reduce the threats to oceanic fisheries posed by climate change and to capitalise on opportunities.  相似文献   

4.
Climatic variability has profound effects on the distribution, abundance and catch of oceanic fish species around the world. The major modes of this climate variability include the El Niño-Southern Oscillation (ENSO) events, the Pacific Decadal Oscillation (PDO) also referred to as the Interdecadal Pacific Oscillation (IPO), the Indian Ocean Dipole (IOD), the Southern Annular Mode (SAM) and the North Atlantic Oscillation (NAO). Other modes of climate variability include the North Pacific Gyre Oscillation (NPGO), the Atlantic Multidecadal Oscillation (AMO) and the Arctic Oscillation (AO). ENSO events are the principle source of interannual global climate variability, centred in the ocean–atmosphere circulations of the tropical Pacific Ocean and operating on seasonal to interannual time scales. ENSO and the strength of its climate teleconnections are modulated on decadal timescales by the IPO. The time scale of the IOD is seasonal to interannual. The SAM in the mid to high latitudes of the Southern Hemisphere operates in the range of 50–60 days. A prominent teleconnection pattern throughout the year in the Northern Hemisphere is the North Atlantic Oscillation (NAO) which modulates the strength of the westerlies across the North Atlantic in winter, has an impact on the catches of marine fisheries. ENSO events affect the distribution of tuna species in the equatorial Pacific, especially skipjack tuna as well as the abundance and distribution of fish along the western coasts of the Americas. The IOD modulates the distribution of tuna populations and catches in the Indian Ocean, whilst the NAO affects cod stocks heavily exploited in the Atlantic Ocean. The SAM, and its effects on sea surface temperatures influence krill biomass and fisheries catches in the Southern Ocean. The response of oceanic fish stocks to these sources of climatic variability can be used as a guide to the likely effects of climate change on these valuable resources.  相似文献   

5.
近年来遥感技术的发展为多圈层中陆面过程和边界层研究提供了有力的工具。文章分析了目前用于陆面过程参数化研究的重要遥感信息源。并评述遥感信息在陆面过程参数化研究中的基本应用和存在问题,最后,提出发展方向和展望。  相似文献   

6.
Sustainable fisheries management into the future will require both understanding of and adaptation to climate change. A risk management approach is appropriate due to uncertainty in climate projections and the responses of target species. Management strategy evaluation (MSE) can underpin and support effective risk management. Climate change impacts are likely to differ by species and spatially. We use a spatial MSE applied to a multi-species data-poor sea cucumber/béche-de-mer fishery to demonstrate the utility of MSE to test the performance of alternative harvest strategies in meeting fishery objectives; this includes the ability to manage through climate variability and change, and meeting management objectives pertaining to resource status and fishery economic performance. The impacts of fishing relative to the impacts of climate change are distinguished by comparing future projection distributions relative to equivalent no-fishing no-climate-change trials. The 8 modelled species exhibit different responses to environmental variability and have different economic value. Status quo management would result in half the species falling below target levels, moderate risks of overall and local depletion, and significant changes in species composition. The three simple strategies with no monitoring (spatial rotation, closed areas, multi-species composition) were all successful in reducing these risks, but with fairly substantial decreases in the average profit. Higher profits (for the same risk levels) could only be achieved with strategies that included monitoring and hence adaptive management. Spatial management approaches based on adaptive feedback performed best overall.  相似文献   

7.
Climate change is expected to bring potentially significant changes to Washington State’s natural, institutional, cultural, and economic landscape. Addressing climate change impacts will require a sustained commitment to integrating climate information into the day-to-day governance and management of infrastructure, programs, and services that may be affected by climate change. This paper discusses fundamental concepts for planning for climate change and identifies options for adapting to the climate impacts evaluated in the Washington Climate Change Impacts Assessment. Additionally, the paper highlights potential avenues for increasing flexibility in the policies and regulations used to govern human and natural systems in Washington.  相似文献   

8.
Managing Arctic marine resources to be resilient to environmental changes requires knowledge of how climate change is affecting marine food webs and fisheries. Changes to fishery resources will have major implications for coastal Indigenous communities whose livelihoods, health, and cultures are strongly connected to fisheries. Understanding these broad social-ecological changes requires a transdisciplinary approach bringing together contrasting and complementary disciplines and ways of knowing. Here, we examine climatic proxies, ecological, and fishery indicators (stable isotopes, fish condition, and lipid content), and interviews with Inuit fishers to assess how marine ecosystem changes have influenced Arctic Char (Salvelinus alpinus) ecology and fisheries over a 30-year time period (1987–2016) in the Kitikmeot region of the Canadian Arctic. Inuit fishers reported several observations of environmental changes, including longer ice-free seasons, warmer ocean temperatures, and the arrival of new marine species. Biophysical data revealed important changes toward earlier dates of ice breakup (>12 days in some areas) and a shift in isotopic niche reflecting a changing Arctic Char diet, with increased contribution of pelagic carbon and higher trophic level prey. Fish condition was improved in years with earlier ice breakup, as observed by both Inuit fishers and biophysical indicators, while lipid content increased through time, suggesting that longer ice-free seasons may have a positive effect on Arctic Char quality as reflected by both fish condition and lipid content. Long-term impacts of continuing climate change, however, such as the northward expansion of boreal species and increasing ocean temperatures, could have negative effects on fisheries (e.g., physiological impairment in fish if temperatures exceed their thermal range). Continuous community-based monitoring that directly informs fisheries management could help communities and managers adaptively, and sustainably, manage in the face of multiple interacting changes in Arctic marine systems.  相似文献   

9.
IPCC-type climate models have produced simulations of the oceanic environment that can be used to drive models of upper trophic levels to explore the impact of climate change on marine resources. We use the Spatial Ecosystem And Population Dynamics Model (SEAPODYM) to investigate the potential impact of Climate change under IPCC A2 scenario on Pacific skipjack tuna (Katsuwonus pelamis). IPCC-type models are still coarse in resolution and can produce significant anomalies, e.g., in water temperature. These limitations have direct and strong effects when modeling the dynamics of marine species. Therefore, parameter estimation experiments based on assimilation of historical fishing data are necessary to calibrate the model to these conditions before exploring the future scenarios. A new simulation based on corrected temperature fields of the A2 simulation from one climate model (IPSL-CM4) is presented. The corrected fields led to a new parameterization close to the one achieved with more realistic environment from an ocean reanalysis and satellite-derived primary production. Projected changes in skipjack population under simple fishing effort scenarios are presented. The skipjack catch and biomass is predicted to slightly increase in the Western Central Pacific Ocean until 2050 then the biomass stabilizes and starts to decrease after 2060 while the catch reaches a plateau. Both feeding and spawning habitat become progressively more favourable in the eastern Pacific Ocean and also extend to higher latitudes, while the western equatorial warm pool is predicted to become less favorable for skipjack spawning.  相似文献   

10.
Dramatic climatic change in the Arctic elevates the importance of determining the risk of exposure for people living in vulnerable areas and developing effective adaptation programs. Climate change assessment reports are valuable, and often definitive, sources of information for decision makers when constructing adaptation plans, yet the scope of these reports is too coarse to identify site-specific exposure to the impacts of climate change and adaptation needs. Subsistence hunters and gatherers in the Arctic are valuable knowledge holders of climate-related change in their area. Incorporating both their traditional ecological knowledge and information found in climate science assessment reports can offer adaption planners a deeper understanding of exposure to climate change and local adaptation needs. In this study, we compare information found in assessment reports of climate change in the Arctic with what we have learned from the Alaskans Sharing Indigenous Knowledge project from 2009 to 2012, a research project documenting traditional ecological knowledge in two Native villages in Alaska, Savoonga and Shaktoolik. Content analysis of the interviews with hunters and gatherers reveal the site-specific impacts of climate change affecting these two villages. We find that their traditional ecological knowledge is complimentary and largely corroborates the climate science found in assessment reports. Traditional ecological knowledge, however, is more current to the social and local conditions of the villages, and presents a more unified social and biophysical portrayal of the impacts of climate change. If taken together, these two forms of knowledge can focus adaptation planning on the pertinent needs of the communities in question.  相似文献   

11.
Small-scale fisheries in developing regions are particularly vulnerable to climate change, but the assessment of climate-induced changes and impacts are often hampered by the data poor-situation of these social-ecological systems. Based on 40 years of scientific and local ecological knowledge, we provide a coherent narrative about the effects of a marine hotspot of climate change on a small-scale fishery across different geographical and temporal scales. We applied a mixed-methods approach to assess biophysical changes, social-ecological impacts, and the incremental spectrum of actions implemented at multiple levels to increase the adaptive capacity of a small-scale clam fishery. The warming hotspot here analyzed was the fastest-warming region in the South Atlantic Ocean. Long-term changes in wind intensity and direction were also noticeable at a regional scale. Both sea surface temperature and winds showed a clear shifting pattern in the late 1990 s. These climate-related stressors determined ecosystem and targeted population changes (e.g. clam mass mortalities, slow stock recovery rates after ecological shocks, habitat narrowing), and favored harmful algal bloom-forming organisms. Climate-induced drivers also affected the human component of the social-ecological system, preventing fishers from securing a fulltime livelihood and limiting the fishery economic potential. Adaptive responses at multiple levels provided some capacity to address climate change effects, and transformative pathways are being taken to adapt to climate-induced changes over the long-term. Transformative changes were fostered by the local perception of environmental change, shared narratives, sustained scientific monitoring programs, and the interaction between knowledge systems, facilitated by a bridging organization within a broader process of governance transformation. The combination of autonomous adaptations (based on linking social capital and fishery leaders agency) and government-led adaptations were essential to face the challenges imposed by climate change. Our results serve as a learning platform to anticipate threats and envision solutions to a wide range of small-scale fisheries in fast-warming regions worldwide.  相似文献   

12.
A potential impact of climate change in the south Asian context in general and the Indian subcontinent in particular is an increase in rainfall, in some areas up to 50%. Using an extensive information base available on the dynamics of landscape structure and function of the northeastern hill areas of India, scenarios on landscape changes, as an adaptation to climate change, have been constructed. Climate change would impose a variety of stresses on sustainable livelihood of the inhabitants of the rain-forested areas through stresses on ecosystem function. It is concluded that appropriate management strategies for natural forests and plantation forestry should go hand in hand with a comprehensive rural ecosystem rehabilitation plan.  相似文献   

13.
The EU project BALANCE (Global Change Vulnerabilities in the Barents region: Linking Arctic Natural Resources, Climate Change and Economies) aims to assess vulnerability to climate change in the Barents Sea Region. As a prerequisite the potential impact of climate change on selected ecosystems of the study area has to be quantified, which is the subject of the present paper. A set of ecosystem models was run to generate baseline and future scenarios for 1990, 2020, 2050 and 2080. The models are based on data from the Regional Climate Model (REMO), driven by a GCM which in turn is forced by the IPCC-B2 scenario. The climate change is documented by means of the Köppen climate classification. Since the multitude of models requires the effect of climate change on individual terrestrial and marine systems to be integrated, the paper concentrates on a standardised visualisation of potential impacts by use of a Geographical Information System for the timeslices 2050 and 2080. The resulting maps show that both terrestrial and marine ecosystems of the Barents region will undergo significant changes until both 2050 and 2080.  相似文献   

14.
Climate change has the potential to increase the challenge of preventing and controlling outbreaks of infectious diseases. An adaptation assessment is an important aspect of designing and implementing policies and measures to avoid, prepare for, and effectively respond to infectious diseases outbreaks. The main steps in conducting an adaptation assessment include: 1) evaluating the effectiveness of policies and measures that address the burden of climate-sensitive infectious diseases; 2) identifying options to manage the health risks of current and projected climate change; 3) evaluating and prioritizing the options; 4) identifying human and financial resources needs, and possible barriers, constraints, and limits to implementation; and 5) developing monitoring and evaluation programs to ensure continued effectiveness of policies and measures in a changing climate. Optimally, relevant stakeholders are optimally included throughout the adaptation assessment. Although the process of conducting an assessment is similar across nations and regions, the context and content will vary depending on local circumstances, socioeconomic conditions, legal and regulatory frameworks, and other factors. The European Centers for Disease Prevention and Control developed guidelines for conducting assessments, with sufficient consistency to facilitate learning lessons across assessments.  相似文献   

15.
Statistical downscaling methods are commonly used to address the scale mismatch between coarse resolution Global Climate Model output and the regional or local scales required for climate change impact assessments. The effectiveness of a downscaling method can be measured against four broad criteria: consistency with the existing baseline data in terms of means, trends and distributional characteristics; consistency with the broader scale climate data used to generate the projections; the degree of transparency and repeatability; and the plausibility of results produced. Many existing downscaling methods fail to fulfil all of these criteria. In this paper we examine a block bootstrap simulation technique combined with a quantile prediction and matching method for simulating future daily climate data. By utilising this method the distributional properties of the projected data will be influenced by the distribution of the observed data, the trends in predictors derived from the Global Climate Models and the relationship of these predictors to the observed data. Using observed data from several climate stations in Vanuatu and Fiji and out-of-sample validation techniques, we show that the method is successful at projecting various climate characteristics including the variability and auto-correlation of daily temperature and rainfall, the correlations between these variables and between spatial locations. This paper also illustrates how this novel method can produce more effective point scale projections and a more credible alternative to other approaches in the Pacific region.  相似文献   

16.
北京气候中心CMIP6数据共享平台及应用   总被引:1,自引:0,他引:1       下载免费PDF全文
为保障北京气候中心(Beijing Climate Center,BCC)气候模式在第6次耦合模式比较计划(Coupled Model Intercomparison Project Phase 6,CMIP6)中的大量试验数据产品面向国内外实现共享,建立了试验数据共享平台。由于模式试验数据具有数据量大、要素种类繁多、元数据多样等特征,为提供高效的数据管理,平台采用分布式存储架构,数据通过气候模式输出重写(climate model output rewriter,CMOR)软件进行格式规范,并实现基于THREDDS(thematic real-time environmental distributed data services)的数据组织与共享。在平台建设及软件设计部署等层面,充分考虑数据安全。该平台实现BCC 3个模式约190 TB的试验数据稳定、高效共享,为国内外气候变化领域科研工作者提供获取数据的方便快捷途径与方法,成为推动我国气候模式国际应用的有力技术手段。  相似文献   

17.
基于CMIP5模式集合预估21世纪中国气候带变迁趋势   总被引:3,自引:0,他引:3  
本文选用耦合模式比较计划第五阶段(CMIP5)数据,结合英国东英吉利大学气候研究中心(CRU)气温和降水资料,分析了中国20世纪末期气候带分布;以此为基础,模拟并分析了RCP2.6和RCP8.5两种情景下中国21世纪中期和末期气候带的变迁趋势。结果表明:CMIP5模式集合数据能较好地模拟出中国区域气温和降水空间分布形态,CRU分析资料描述的气候带分布与柯本气候分类吻合较好。21世纪中期、末期与20世纪末期相比,RCP2.6情景下,气候类型及分布变化并不显著,RCP8.5情景下,热夏冬干温暖型分别增加了28.2%(中期)、86.9%(末期),草原气候分别增加了24.1%(中期)、49.4%(末期)。热夏冬干冷温型到21世纪末期有明显的增加,但苔原气候和沙漠气候类型所占比重减少。  相似文献   

18.
Climate change caused by anthropogenic activities has generated a variety of research focusing on investigating the past climate, predicting the future climate and quantifying the change in climate extreme events by using different climate models. Climate extreme events are valuable to evaluate the potential impact of climate change on human activities, agriculture and economy and are also useful to monitor the climate change on global scale. Here, a Regional Climate Model (RCM) simulation is used to study the future variations in the temperature extreme indices, particularly change in frequency of warm and cold spells duration over Pakistan. The analyses are done on the basis of simulating two 30 years simulations with the Hadley Center’s RCM PRECIS, at a horizontal resolution of 50 km. Simulation for the period 1961–1990 represents the recent climate and simulation for the period 2071–2100 represents the future climate. These simulations are driven by lateral boundary conditions from HadAM3P GCM of Hadley centre UK. For the validation of model, observed mean, maximum and minimum temperatures for the period 1961–1990 at all the available stations in Pakistan are first averaged and are then compared with the PRECIS averaged grid-box data. Also the observed monthly gridded data set of Climate Research Unit (UK) data is used to validate the model. Temperature indices in the base period as well as in future are then calculated and the corresponding change is observed. Percentile based spatial change of temperature shows that in summer, increase in daily minimum temperature is more as compared to the increase of daily maximum temperature whereas in winter, the change in maximum temperature is high. The occurrence of annual cold spells shows significantly decreasing trend while for warm spells there is slight increasing trend over Pakistan.  相似文献   

19.
Hydrological models of the Great Lakes basin were used to study the sensitivity of Great Lakes water supplies to climate warming by driving them with meteorological data from four U.S. climate zones that were transposed to the basin. Widely different existing climates were selected for transposition in order to identify thresholds of change where major impacts on water supplies begin to occur and whether there are non-linear responses in the system. The climate zones each consist of 43 years of daily temperature and precipitation data for 1,000 or more stations and daily evaporation-related variables (temperature, wind speed, humidity, cloud cover) for approximately 20–35 stations. A key characteristic of these selected climates was much larger variability in inter-annual precipitation than currently experienced over the Great Lakes. Climate data were adjusted to simulate lake effects; however, a comparison of hydrologic results with and without lake effects showed that there was only minor effects on water supplies.  相似文献   

20.
Climate change in the European region during the twentieth and twenty-first centuries is analyzed according to Feddema’s method. Precipitation and air temperature data from the twentieth century are taken from the Climatic Research Unit, while data for the twenty-first century are taken from the ENSEMBLES climate change project. The latter were bias-corrected to ensure homogeneity across the twentieth and twenty-first centuries. Climate classes based on monthly and annual values of potential evapotranspiration, precipitation and their ratio, are defined for 30-year averages, from which trend and spatial agreement analysis are calculated. There are separate classes for annual values and for intra-annual variation. The results indicate that the change of annual climate characteristics will be much more intense in the twenty-first than it was in the twentieth century. The dominant process in the projections is warming, mostly via cold to cool (about 45% of grid points) in north Europe and cool to warm (about 8% of grid points) transformations. The second most important process is the drying of moderately moist classes affecting about 10% of the grid points in south Europe. Changes in intra-annual variability classes are more common than changes in the annual ones during the twentieth century. The chance of increase in intra-annual temperature variation from high to extreme is about 5% during the course of the twentieth century, and about 10% in the following century.  相似文献   

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