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The latest scientific findings indicate that the increased concentration of greenhouse gases emitted by anthropogenic sources is significantly altering the balance of the global climate system. Considering forecasts of changes in the hydrological cycle and temperature related to global warming, the dynamics governing the functioning of the Pantanal Wetland, responsible for its rich biodiversity, find themselves threatened. Thus, this study was designed in the space-time of the Pantanal people called pantaneiros, and aims to discuss the Traditional Ecological Knowledge (TEK) of the Traditional Community Cuiabá Mirim regarding climate change. The information presented was obtained from 22 pantaneiros, between March 2008 and March 2010. The population sample was selected by the Snow Ball method. For data collection, semi structured interviews and oral histories were used. The results were compared with observations, simulations and projections of the IPCC AR4 for the region. The main findings of this research indicate that TEK presents itself as a crucial and complementary source of information for the development of local/regional adaptation strategies to climate change, bringing a distinct and relevant point of view from vulnerable stakeholders to the decision makers.  相似文献   

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Abstract

The first substantial radiative effects of the El Chichón volcanic cloud were observed in Fairbanks in the winter of 1982/83. Winter is the time when stratospheric temperatures can vary widely owing to sudden stratospheric warmings, and interannual variations are large. Mean monthly temperatures of the stratosphere were analysed for the 50‐, 40‐, 30‐, 25‐, 20‐, 15‐, and 10‐mb levels, with the greatest density of the volcanic cloud expected to be around the 20‐mb level. For the four winter months, December 1982 to March 1983, an increase in temperature was observed. This increase was not only observed in Fairbanks, but also for two other stations (McGrath and Anchorage) close by, for which we also analysed the stratospheric temperatures.

Further, the interdiurnal variation of temperature (the radiosonde ascents are made at 0200 and 1400 local time) showed marked and significant increases for all three stations. This can be explained by the fact that during daytime the volcanic cloud is warmed by absorption of solar radiation, while at night no substantial temperature effect for this layer was detected.  相似文献   

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The knowledge of the climatic conditions of a region is crucial for its agricultural development. It is also extremely important for understanding the fact that certain cultures have to develop under prevailing temperature and humidity conditions and assist in the adoption of a suitable irrigation technique, as well as its management and operationalization. The K?ppen system of climate classification is widely used for the identification of homogeneous climate zones as it considers only rainfall and temperature as the meteorological elements for classification. For this study, we used climatic databases of rainfall and temperature in a raster format, with a spatial resolution of 30″ of arc (an approximate area of 0.86?km2?pixel?1), from 1961 to 1990. Through geoprocessing techniques, we obtained a map of climatic classification for the state of Minas Gerais. We found that the state has the following three major climatic groups: A, B and C, which correspond to tropical rainy, dry and warm temperate climates, respectively. The climate classes obtained were Aw, Am, BSh, Cwa and Cwb, with Aw, Cwa and Cwb classes occupying 99.89% of the territorial area of the state. The validation of the results showed a satisfactory agreement, with 93.75% reliability.  相似文献   

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In middle and high latitudes, climate change could impact the frequency and characteristics of frontal passages. Although transitions between air masses are significant features of the general circulation that influence human activities and other surface processes, they are much more difficult to objectively identify than single variables like temperature or even extreme events like fires, droughts, and floods. The recently developed Spatial Synoptic Classification (SSC) provides a fairly objective means of identifying frontal passages. In this research, we determine the specific meteorological patterns represented by the SSC??s Transition category, a ??catch-all?? group that attempts to identify those days that cannot be characterized as a single, homogeneous air mass type. The result is a detailed transition climatology for the continental USA. We identify four subtypes of the Transition category based on intra-day sea level pressure change and dew point temperature change. Across the contiguous USA, most transition days are identified as cold fronts and warm fronts during the winter season. Among the two less common subtypes, transition days in which the dew point temperature and pressure both rise are more frequently observed across the western states, and days in which both variables fall are more frequently observed in coastal regions. The relative frequencies of wintertime warm and cold fronts have changed over the period 1951?C2007. Relative cold front frequency has significantly increased in the Northeast and Midwest regions, and warm front frequencies have declined in the Midwest, Rocky Mountain, and Pacific Northwest regions. The overall shift toward cold fronts and away from warm fronts across the northern USA arises from a combination of an enhanced ridge over western North America and a northward shift of storm tracks throughout the mid-latitudes. These results are consistent with projections of climate change associated with elevated greenhouse gas concentrations.  相似文献   

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Sharon Mascher 《Climate Policy》2018,18(8):1012-1027
The Pan-Canadian Framework on Clean Growth and Climate Change is designed to put Canada on track to meet its Paris commitments. A key pillar of the plan is the introduction of a pan-Canadian carbon price by the end of 2018. However, four Canadian provinces, nearly 85% of the Canadian economy and population, have already implemented carbon pricing systems. British Columbia (BC) has a carbon tax. Alberta is transitioning from an output-based allocation system for industrial emitters to a hybrid system combining a carbon levy and refined output-based system. Québec and Ontario have implemented cap-and-trade systems, linked to California. Recognizing these existing systems, rather than impose a single carbon pricing mechanism, the Pan-Canadian Approach to Carbon Pricing gives provinces and territories the flexibility to adopt a carbon tax, a hybrid system, or a cap-and-trade system. To address concerns relating to ‘fairness’ and equivalency of carbon price, a federal carbon pricing benchmark establishes criteria relating to minimum ‘common scope’ and ‘increases in stringency’ that provincial and territorial carbon pricing systems must meet. This article explores the design features of the existing Alberta, BC, Ontario and Québec carbon pricing systems, and considers how the benchmark affects stringency and addresses equivalency of carbon price across these different systems.

Key policy insights

  • Canada is taking advantage of its federal structure of government to introduce a minimum pan-Canadian carbon price of $10/tCO2e in 2018, rising by $10/year to $50/tCO2e in 2022.

  • Rather than imposing a uniform pricing mechanism, the Canadian federal government is recognizing existing subnational carbon pricing mechanisms with very different design features – BC’s carbon tax, Québec and Ontario’s cap-and-trade systems, and Alberta’s hybrid system – to deliver the pan-Canadian carbon price.

  • In order to deliver a minimum level of increasing stringency and to address issues of equivalency of carbon price across sub-national jurisdictions, the federal government is in the early stages of implementing a federal carbon-pricing benchmark.

  • The lessons learned from the Canadian experience will be relevant to harmonizing carbon pricing systems across both other federal jurisdictions and countries.

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China plans to launch its nationwide Emissions Trading Scheme (ETS) in 2017. Uncertainty in China’s future economic growth rate and its effect on underlying emissions may need to be addressed to ensure stability of the scheme. This article investigates an ex-post cap adjustment mechanism for China’s ETS. An applicable rule for indexation of emissions targets to gross domestic product (GDP) adjustment is presented. Such an ex-post optimal emissions intensity target is estimated in an empirical simulation of the Hubei ETS, a large pilot scheme in a fast-growing Chinese province. And its implications for China’s planned national ETS have been discussed. The article finds that by correcting the emissions cap for the difference between expected and realized GDP, the ex-post adjustment can minimize the abatement costs. It can also limit the influence of uncertainties, as it minimizes the standard deviation of realized abatement, abatement cost, and allowance price for a given expected emissions reduction. In addition, with a limited number of parameters requiring estimation, the ex-post cap adjustment mechanism is feasible. It is consistent with the anticipated design of China’s planned national ETS and could be used alongside other design options such as price corridors.

POLICY RELEVANCE

It will be important for the stability of China’s planned national ETS to address uncertainty about future GDP growth which can significantly affect underlying emissions growth. This paper proposes a specific solution, namely an ex-post cap adjustment mechanism for the ETS cap. This method provides flexibility with transparent rules, would be consistent with China’s overall ETS policy design, and could be implemented in practice as the required parameters can be readily estimated.  相似文献   


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It is crucial to appropriately determine turbulent fluxes in numerical models. Using data collected in East Antarctica from 8 April to 26 November 2016, this study evaluates parameterization schemes for turbulent fluxes over the landfast seaice surface in five numerical models. The Community Noah Land Surface Model with Multi-Parameterizations Options(Noah_mp) best replicates the turbulent momentum flux, while the Beijing Climate System Model(BCC_CSM) produces the optimum sensible and latent hea...  相似文献   

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Hydrofluorocarbons(HFCs) have been widely used in China as substitutes for ozone-depleting substances,the production and use of which are being phased out under the Montreal Protocol.China is a major consumer of HFCs around the world,with its HFC emissions in CO_2-equivalent contributing to about 18% of the global emissions for the period2012-16.Three methods are widely used to estimate the emissions of HFCs-namely,the bottom-up method,top-down method and tracer ratio method.In this study,the tracer ratio method was adopted to estimate HFC emissions in the Yangtze River Delta(YRD),using CO as a tracer.The YRD region might make a significant contribution to Chinese totals owing to its rapid economic growth.Weekly flask measurements for ten HFCs(HFC-23,HFC-32,HFC-125,HFC-134 a,HFC-143 a,HFC-152 a,HFC-227 ea,HFC-236 fa,HFC-245 fa and HFC-365 mfc) were conducted at Lin'an Regional Background Station in the YRD over the period 2012-16,and the HFC emissions were 2.4±1.4 Gg yr~(-1) for HFC-23,2.8±1.2 Gg yr~(-1) for HFC-32,2.2±1.2 Gg yr~(-1) for HFC-125,4.8±4.8 Gg yr~(-1) for HFC-134 a,0.9±0.6 Gg yr~(-1) for HFC-152 a,0.3±0.3 Gg yr~(-1) for HFC-227 ea and 0.3±0.2 Gg yr~(-1) for HFC-245 fa.The YRD total HFC emissions reached 53 Gg CO_2-e yr~(-1),contributing 34% of the national total.The per capita HFC CO_2-equivalent emissions rate was 240 kg yr-1,while the values of per unit area emissions and per million GDP emissions reached 150 Mg km~(-2)yr~(-1) and 3500 kg yr~(-1)(million CNY GDP)-1,which were much higher than national or global levels.  相似文献   

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Theoretical and Applied Climatology - The present work had the objective to determine the tendency and the influence percentage of climatic variables on the Temperature and Humidity Index (THI) in...  相似文献   

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Study of the Optimal Precursors for Blocking Events   总被引:2,自引:0,他引:2  
The precursors of dipole blocking are obtained by a numerical approach based upon a quasi-geostrophic barotropie planetary- to synoptic-scale interaction model without topography and with a localized synopticscale wave-maker. The optimization problem related to the precursors of blocking is formulated and the nonlinear optimization method is used to examine the optimal synoptic-scale initial field successfully. The results show that the prominent characteristics of the optimal synoptic-scale initial field are that the synoptic-scale wave train structures exist upstream of the incipient blocking. In addition, the large-scale low/high eddy-forcing pattern upstream of the incipient blocking is an essential precondition for the onset of dipole blocking.  相似文献   

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马艳  陈尚 《大气科学进展》2007,24(5):863-874
The simulations were performed using a modified mesoscale model,the Polar MM5,which was adapted for use within polar regions.The objective of the study was to illustrate the skill of the Polar MM5 in simulating atmospheric behavior over the Arctic river basins.Automatic weather station data,global atmospheric analyses,as well as near-surface and upper-air observations were used to verify the simulation. Parallel simulations of the Polar MM5 and the original MM5 within the period 19-29 April 1997 simula- tions revealed that Polar MM5 reproduced better near-surface variables forecasts than the original MM5 for the region located over the North American Arctic regions.The well predicted near-surface temperature and mixing ratio by the Polar MM5 confirmed the modified physical parameterization schemes that were used in this model are appropriate for the Arctic river regions.Then the extended evaluations of the Polar MM5 simulations over both the North American and Eurasian domains during 15 December 2002 to 15 May 2003 were then carried out.The time series plots and statistical analyses from the observations and the Polar MM5 simulations at 16 stations for the near-surface and vertical profiles at 850 hPa and 500 hPa variables were analyzed.The model was found to reproduce the observed atmospheric state both at magnitude and variability with a high degree of accuracy,especially for temperature and near-surface winds,although there was a slight cold bias that existed near the surface.  相似文献   

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The relaxed eddy accumulation (REA) method is an attractive alternative to the eddy covariance method to measure trace-gas flux, because it allows the use of analyzers with an optimal integration time to reduce the noise. However, the use of an empirical coefficient b results in uncertainties in the REA method. The consistency of b for temperature was investigated using a 1 year dataset obtained at three forest sites in East Asia: a temperate evergreen coniferous forest, a tropical evergreen broadleaf forest, and a cool-temperate deciduous coniferous forest. The observational b ranged from 0.54 to 0.57 under unstable conditions. Although the values for observational b were within narrow ranges among the sites, there were slight site-specific differences. We introduced new expression of b, similarity b, based on scalar similarity using the integral turbulence characteristics to investigate the nature of b. Both the observational and similarity b increased with increasing atmospheric stability under stable conditions, when lower values for the standard deviation of the vertical wind velocity resulted in higher values for b. The variations in b under stable conditions differed among sites. There were no seasonal variations in the observational b at all sites. Consequently, the present study recommends determining the coefficient b for unstable conditions for each site and considering changes in b associated with atmospheric stability in order to minimize errors in the REA method.  相似文献   

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