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1.
《Climate Policy》2013,13(6):652-668
Sectoral approaches have been gaining currency in the international climate debate as a possible remedy to the shortfalls of the Kyoto Protocol. Proponents argue that a sector-based architecture can more easily invite the participation of developing countries, address competitiveness issues, and enable immediate emissions reductions. However, given the numerous proposals, much confusion remains as to what sectoral approaches actually are. This article provides a simple, yet comprehensive, taxonomy of the various proposals for sectoral approaches. Based on the dual criteria of content and actors, three such types are identified and described: government targets and timetables; industry targets and timetables; and transnational technology cooperation. For each of these types, existing proposals and ongoing initiatives are discussed. In a second step, the article analyses the political landscape in which sectoral approaches are being debated, identifying the interests of their key advocates as well as the concerns of their critics. The Japanese government and energy-intensive manufacturing industries represent the main proponents of sectoral approaches to address the problems of carbon leakage and economic competitiveness. Developing countries, on the other hand, are wary of attempts to impose emissions reduction targets on their economies through sectoral target-setting. They, therefore, interpret sectoral approaches as sector-based forms of technology cooperation and technology transfer. 相似文献
2.
MALIK AMIN ASLAM KHAN 《Climate Policy》2013,13(2):162-165
The climate change issue faces a big challenge, perhaps the biggest challenge of all—politics. Pakistan has taken many noticeable steps in relation to climate change: (1) it is the only country in which the Prime Minister is heading an inter-ministerial task force on climate change, (2) it is the first developing country to establish a specialized, self-financed scientific centre to research the impact of climate change, and (3) it is the lead country to earmark budgetary funds for a national carbon sequestration programme. Pakistan, together with many developing countries, has much to offer the climate change issues. The author proposes five approaches to build consensus among climate policy negotiators: (1) reinforcing the polluter pays principle and ‘common but differentiated responsibility’, (2) active partnership by developing countries, (3) recognizing the voluntary actions taken by developing countries, (4) reinforcing the issue of adaptation, and (5) considering the option of equal per capita entitlements. 相似文献
3.
Weather services base their operational definitions of “present” climate on past observations, using a 30-year normal period
such as 1961–1990 or 1971–2000. In a world with ongoing global warming, however, past data give a biased estimate of the actual
present-day climate. Here we propose to correct this bias with a “delta change” method, in which model-simulated climate changes
and observed global mean temperature changes are used to extrapolate past observations forward in time, to make them representative
of present or future climate conditions. In a hindcast test for the years 1991–2002, the method works well for temperature,
with a clear improvement in verification statistics compared to the case in which the hindcast is formed directly from the
observations for 1961–1990. However, no improvement is found for precipitation, for which the signal-to-noise ratio between
expected anthropogenic changes and interannual variability is much lower than for temperature. An application of the method
to the present (around the year 2007) climate suggests that, as a geographical average over land areas excluding Antarctica,
8–9 months per year and 8–9 years per decade can be expected to be warmer than the median for 1971–2000. Along with the overall
warming, a substantial increase in the frequency of warm extremes at the expense of cold extremes of monthly-to-annual temperature
is expected. 相似文献
4.
In this paper we argue that the financial provisions of the Copenhagen Accord, if used primarily to mitigate greenhouse gas (GHGs) emissions, could compensate the lack of more energetic action on the domestic mitigation side. In order to maximize the mitigation potential, the Copenhagen Green Climate Fund (CGCF) should be transformed into the International Bank for Emissions Allowance Acquisition (IBEAA) envisaged by Bradford (2008). We estimate that 50 percent of the CGCF in 2020 (50 US billions) could finance from 2.1 to 3.3?Gt CO2-eq emission reductions, depending on the domestic mitigation effort of Annex I and Non-Annex I countries. We construct a matrix that shows the level of GHGs emissions in 2020 under all possible combinations of abatement pledges and international mitigation financing, thus highlighting a rich set of options to reach the same level of GHGs emissions in 2020. 相似文献
5.
A. Henderson-Sellers 《Climatic change》1993,23(4):337-377
A simplified vegetation distribution prediction scheme is used in combination with the Biosphere-Atmosphere Transfer Scheme (BATS) and coupled to a version of the NCAR Community Climate Model (CCM1) which includes a mixed-layer ocean. Employed in an off-line mode as a diagnostic tool, the scheme predicts a slightly darker and slightly rougher continental surface than when BATS' prescribed vegetation classes are used. The impact of tropical deforestation on regional climates, and hence on diagnosed vegetation, differs between South America and S.E. Asia. In the Amazon, the climatic effects of removing all the tropical forest are so marked that in only one of the 18 deforested grid elements could the new climate sustain tropical forest vegetation whereas in S.E. Asia in seven of the 9 deforested elements the climate could continue to support tropical forest. Following these off-line tests, the simple vegetation scheme has been coupled to the GCM as an interactive (or two-way) submodel for a test integration lasting 5.6 yr. It is found to be a stable component of the global climate system, producing only ~ 3% (absolute) interannual changes in the predicted percentages of continental vegetation, together with globally-averaged continental temperature increases of up to + 1.5 °C and evaporation increases of 0 to 5 W m–2 and no discernible trends over the 67 months of integration. On the other hand, this interactive land biosphere causes regional-scale temperature differences of ± 10 °C and commensurate disturbances in other climatic parameters. Tuning, similar to the q-flux schemes used for ocean models, could improve the simulation of the present-day surface climate but, in the longer term, it will be important to focus on predicting the characteristics of the continental surface rather than simple vegetation classes. The coupling scheme will also have to allow for vegetation responses occurring over longer timescales so that the coupled system is buffered from sudden shocks. 相似文献
6.
Earlier GCM studies have expressed the concern that an enhancement of greenhouse warming might increase the occurrence of summer droughts in mid-latitudes, especially in southern Europe and central North America. This could represent a severe threat for agriculture in the regions concerned, where summer is the main growing season. These predictions must however be considered as uncertain, since most studies featuring enhanced summer dryness in mid-latitudes use very simple representations of the land-surface processes ("bucket" models), despite their key importance for the issue considered. The current study uses a regional climate model including a land-surface scheme of intermediate complexity to investigate the sensitivity of the summer climate to enhanced greenhouse warming over the American Midwest. A surrogate climate change scenario is used for the simulation of a warmer climate. The control runs are driven at the lateral boundaries and the sea surface by reanalysis data and observations, respectively. The warmer climate experiments are forced by a modified set of initial and lateral boundary conditions. The modifications consist of a uniform 3 K temperature increase and an attendant increase of specific humidity (unchanged relative humidity). This strategy maintains a similar dynamical forcing in the warmer climate experiments, thus allowing to investigate thermodynamical impacts of climate change in comparative isolation. The atmospheric CO 2 concentration of the sensitivity experiments is set to four times its pre-industrial value. The simulations are conducted from March 15 to October 1st, for 4 years corresponding to drought (1988), normal (1986, 1990) and flood (1993) conditions. The numerical experiments do not present any great enhancement of summer drying under warmer climatic conditions. First, the overall changes in the hydrological cycle (especially evapotranspiration) are of small magnitude despite the strong forcing applied. Second, precipitation increases in spring lead to higher soil water recharge during this season, compensating for the enhanced soil moisture depletion occurring later in the year. Additional simulations replacing the plant control on transpiration with a bucket-type formulation presented increased soil drying in 1988, the drought year. This suggests that vegetation control on transpiration might play an important part in counteracting an enhancement of summer drying when soil water gets limited. Though further aspects of this issue would need investigating, our results underline the importance of land-surface processes in climate integrations and suggest that the risk of enhanced summer dryness in the region studied might be less acute than previously assumed, provided the North American general circulation does not change markedly with global warming. 相似文献
7.
《Atmospheric Research》1988,22(1):73-84
Computation of solar radiation flux within a fog layer is essential during the dissipation stage. A new parameterization of the asymmetry factor g and of the single scattering albedo ω allows the use of a monospectral model (FB), already designed for cloudy layer by Fouquart and Bonnel (1980). This new parameterization is necessary because of the different droplet size distributions existing in clouds and fogs. A calculation method of new g and ω values, in function of the optical thickness δ and of the effective radius re of droplet size distribution is proposed. 相似文献
8.
Nándor Fodor Ildikó Dobi János Mika László Szeidl 《Meteorology and Atmospheric Physics》2010,107(3-4):91-101
This paper presents a new stochastic multi-variable weather generator (MV-WG) and compares its performance with LARS-WG version 4.0. Daily data of 109 meteorological stations from a North American database were used in a twofold comparison of the two generators: (1) the capability of reproducing the mean and variance of annual, seasonal and monthly values, and (2) the capability of reproducing extreme weather events were compared. Both generators did very well on imitating the mean and the variance of the monthly values of the investigated variables, but both showed a more moderate performance as far as the generation of extreme events was concerned. The three-parameter Weibull function, which is first introduced in MV-WG, was found to be a powerful tool to describe not only the distribution of the daily precipitation amounts, but also the distribution of dry and wet spell lengths, as well. 相似文献
9.
We estimate the effects of climatic changes, as predicted by six climate models, on lake surface temperatures on a global scale, using the lake surface equilibrium temperature as a proxy. We evaluate interactions between different forcing variables, the sensitivity of lake surface temperatures to these variables, as well as differences between climate zones. Lake surface equilibrium temperatures are predicted to increase by 70 to 85 % of the increase in air temperatures. On average, air temperature is the main driver for changes in lake surface temperatures, and its effect is reduced by ~10 % by changes in other meteorological variables. However, the contribution of these other variables to the variance is ~40 % of that of air temperature, and their effects can be important at specific locations. The warming increases the importance of longwave radiation and evaporation for the lake surface heat balance compared to shortwave radiation and convective heat fluxes. We discuss the consequences of our findings for the design and evaluation of different types of studies on climate change effects on lakes. 相似文献
10.
Carolyn Kousky 《Climatic change》2014,124(1-2):9-20
As sea level rises, coastal communities will face increased risks of flooding, storm surge, and inundation. In some areas, structural protective measures will be built, and for some properties, accommodation to sea level rise may be possible. For other areas, however, some form of retreat will be either preferred on economic or sociopolitical grounds or required given fiscal constraints. This paper considers how society can proactively manage shoreline retreat in those locations where it is deemed the preferable policy. A three-part strategy is proposed: (1) reduce new development in the highest-risk areas; (2) adopt policies that allow for expected and orderly removal or modification of development as inundation occurs; and (3) take advantage of disasters to implement managed retreat approaches. Specific policies are recommended and the challenges of institutional change discussed. 相似文献
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13.
T. N. Venkatesh Joseph Mathew Ravi S. Nanjundiah 《Meteorology and Atmospheric Physics》2014,126(3-4):139-160
Many theories and mechanisms have been proposed to explain the phenomenon of clear-air turbulence (CAT), and some of them have been successful in predicting light, moderate and, in some cases, severe turbulence. It is only recently that skill in the forecasting of the severe form of CAT, which could lead to injuries to passengers and damage to aircraft, has improved. Recent observations and simulations suggest that some severe to extreme turbulence could be caused by horizontal vortex tubes resulting from secondary instabilities of regions of high shear in the atmosphere. We have conducted direct numerical simulations to understand the scale relationship between primary structures (larger-scale structures related to one of the causes mentioned above) and secondary structures (smaller-sized, shear structures of the size of aircraft). From shear layer simulations, we find that the ratio of sizes of primary and secondary vortices is of the right order to generate aircraft-scale vortex tubes from typical atmospheric shear layers. We have also conducted simulations with a mesoscale atmospheric model, to understand possible causes of turbulence experienced by a flight off the west coast of India. Our simulations show the occurrence of primary flow structures related to synoptic conditions around the time of the incident. The evidence presented for this mechanism also has implications for possible methods of detection and avoidance of severe CAT. 相似文献
14.
An analysis is presented of an ensemble of regional climate model (RCM) experiments from the ENSEMBLES project in terms of mean winter snow water equivalent (SWE), the seasonal evolution of snow cover, and the duration of the continuous snow cover season in the European Alps. Two sets of simulations are considered, one driven by GCMs assuming the SRES A1B greenhouse gas scenario for the period 1951–2099, and the other by the ERA-40 reanalysis for the recent past. The simulated SWE for Switzerland for the winters 1971–2000 is validated against an observational data set derived from daily snow depth measurements. Model validation shows that the RCMs are capable of simulating the general spatial and seasonal variability of Alpine snow cover, but generally underestimate snow at elevations below 1,000 m and overestimate snow above 1,500 m. Model biases in snow cover can partly be related to biases in the atmospheric forcing. The analysis of climate projections for the twenty first century reveals high inter-model agreement on the following points: The strongest relative reduction in winter mean SWE is found below 1,500 m, amounting to 40–80 % by mid century relative to 1971–2000 and depending upon the model considered. At these elevations, mean winter temperatures are close to the melting point. At higher elevations the decrease of mean winter SWE is less pronounced but still a robust feature. For instance, at elevations of 2,000–2,500 m, SWE reductions amount to 10–60 % by mid century and to 30–80 % by the end of the century. The duration of the continuous snow cover season shows an asymmetric reduction with strongest shortening in springtime when ablation is the dominant factor for changes in SWE. We also find a substantial ensemble-mean reduction of snow reliability relevant to winter tourism at elevations below about 1,800 m by mid century, and at elevations below about 2,000 m by the end of the century. 相似文献
15.
This paper critically reviews and intercompares land surface schemes (LSSs) as used in atmospheric general circulation models
(AGCMs) to simulate soil moisture and its response to a warmer climate, and potential evapotranspiration approaches as used
in operational soil moisture monitoring and in predicting the response of soil moisture to a warmer climate. AGCM predictions
of overall soil moisture change are in broad agreement but disagree sharply in some regions. Intercomparison projects have
sought to evaluate the LSSs used by AGCMs for both accuracy and consistency. These studies have found that different LSSs
can produce very different simulations even when supplied with identical atmospheric forcing. As well, LSSs that produce similar
surface results from present-day or control climates often diverge when forced with climatic change data. Furthermore, no
single LSS has been identified that produces an adequate simulation of all of temperature, moisture, evapotranspiration and
runoff. AGCM LSSs must resolve the surface energy balance (SEB) in order to compute realistic heat fluxes between with the
atmospheric model. LSSs have been used with AGCMs in both on-line (fully coupled) and off-line modes. In off-line climatic
change experiments, AGCM predictions of atmospheric temperature and precipitation have been used, along with model downward
radiative fluxes at the surface, to drive their own uncoupled LSS. However, there are simple non-energy-balance methods for
estimating evapotranspiration that have been traditionally used in agricultural and meteorological applications. These schemes
compute a potential evapotranspiration (PE) based on temperature and/or net radiation inputs, with the PE modified based on
the availability of soil moisture. Operational PE approaches have also been used with AGCM data in off-line climate change
experiments. The advantages of this approach are that it is simpler and requires less information, although (like the off-line
SEB approach) it leaves out the simulation of feedbacks between the surface and the atmosphere.Although the SEB approach is
essential for LSSs that must be coupled to AGCMs, this does not necessarily make it superior to an off-line operational PE
LSS when it comes to quantities such as soil moisture. The quality of current observational data is insufficient to demonstrate
that either approach is better than the other. Both approaches should continue to be used and intercompared when predicting
the impacts of climatic change on soil moisture. 相似文献
16.
Adapting agriculture to climate change: a review 总被引：2，自引：0，他引：2
Muhuddin Rajin Anwar De Li Liu Ian Macadam Georgina Kelly 《Theoretical and Applied Climatology》2013,113(1-2):225-245
The agricultural sector is highly vulnerable to future climate changes and climate variability, including increases in the incidence of extreme climate events. Changes in temperature and precipitation will result in changes in land and water regimes that will subsequently affect agricultural productivity. Given the gradual change of climate in the past, historically, farmers have adapted in an autonomous manner. However, with large and discrete climate change anticipated by the end of this century, planned and transformational changes will be needed. In light of these, the focus of this review is on farm-level and farmers responses to the challenges of climate change both spatially and over time. In this review of adapting agriculture to climate change, the nature, extent, and causes of climate change are analyzed and assessed. These provide the context for adapting agriculture to climate change. The review identifies the binding constraints to adaptation at the farm level. Four major priority areas are identified to relax these constraints, where new initiatives would be required, i.e., information generation and dissemination to enhance farm-level awareness, research and development (R&D) in agricultural technology, policy formulation that facilitates appropriate adaptation at the farm level, and strengthening partnerships among the relevant stakeholders. Forging partnerships among R&D providers, policy makers, extension agencies, and farmers would be at the heart of transformational adaptation to climate change at the farm level. In effecting this transformational change, sustained efforts would be needed for the attendant requirements of climate and weather forecasting and innovation, farmer’s training, and further research to improve the quality of information, invention, and application in agriculture. The investment required for these would be highly significant. The review suggests a sequenced approach through grouping research initiatives into short-term, medium-term, and long-term initiatives, with each initiative in one stage contributing to initiatives in a subsequent stage. The learning by doing inherent in such a process-oriented approach is a requirement owing to the many uncertainties associated with climate change. 相似文献
17.
18.
Richard Leduc Michel Ferland Jacques Gariepy Ghislain Jacques Claude Lelievre Gaston Paulin 《Boundary-Layer Meteorology》1980,19(4):471-480
This paper studies the urban heat island in Quebec City and its suburbs on one summer night. The region under study covers an area of 20 km by 20 km which streches from lake Saint-Charles on the north to Levis on the south and from the western suburb of Cap-Rouge to Beauport on the east. The total population of the region is about 400 000.On August 22, 1979 from 22:00 to 23:30 EDT, 109 measurements of wet- and dry-bulb temperatures were taken at preselected points. On that day, a large high pressure system gave clear skies to central Quebec while Quebec City Airport recorded a maximum temperature of 23 °C. The average wind measured at Duberger meteorological tower between 6 and 121 m above ground was 1.8 m s-1 at 22:00 EDT and 0.9 m s-1 at 23:30 EDT. Additional data were obtained from three thermographs installed at strategic points and five regular climatological stations, which were used to estimate cooling rates.During the period of measurement, the cooling rate averaged over the eight reference points was about 0.7 °C h-1. However, the maximum cooling rate, which occured earlier, ranged from 2.2 °C h-1 at Duberger to 4.4 °C h-1 at Courville-de-Poissy. No relation seems to exist, in our case, between the maximum cooling rate and the heat island spatial structure. Comparison of these results with the ones given by Oke et al. (1972) shows that the eight stations behaved more like rural stations than urban ones.The temperature gradient measured between the center of old Quebec City and the suburbs averaged 6 °C while it was 9 °C for the coldest spot. Clo units were used to characterize the microclimates prevailing on the region for that night; 1 clo would be sufficient for comfort downtown while 1.5 clo is needed in the coldest spot for a slowly walking person. Large open areas like parks or the Laval University campus had a definite effect on temperature.The humidity was calculated for each point using standard psychrometric tables; no significant difference could be found over the area expect at points near or above the St. Laurent river where the average dew point was 1.5 °C higher.Each point was classified into 6 categories according to its predominant land-use as reported by the observers. A multiple regression between temperature on the one hand and altitude and land-use on the other hand was tried; it showed that temperature was significantly correlated with both. Such an equation could be used by town-planners to locate temperature gradients in future urban development over the area; land uses could be planned to enhance or reduce these gradients.This study confirms the idea that urban climate is a mosaic of interacting micro-climates. More measurements, including possibly airborne infra-red thermal imagery, will be taken during winter in order to assess the winter urban climate of Quebec City. 相似文献
19.
Summary ?Evapotranspiration characteristics on the point-scale (several hundred square meters) and the local scale (several square
kilometers) are analysed by comparing a deterministic and a statistical – deterministic surface energy balance model. The
vegetation surface variability is represented by both the surface heterogeneity and inhomogeneity. Heterogeneity means the
mosaic of wet (wif ≠ 0) and dry (1-wif) fractions of vegetation surface, while inhomogeneity addresses small scale variations of soil moisture content.
The microscale characteristics of evapotranspiration are considered in terms of analysing evapotranspiration E
v
versus soil moisture content θ, relative frequency distribution characteristics of E
v
(θ) and the aggregation algorithms for its estimation. The analyses are performed for loam soil type under different atmospheric
forcing conditions.
The main result is as follows: For dry vegetation surface (wif = 0), the relationship between the aggregated (θagg) and the area-averaged (θ
m
) soil moisture content is nonlinear and depends on both the states of the surface and the atmospheric forcing conditions.
In the study, we assumed that there are no advective effects and mesoscale circulation patterns induced by surface discontinuities.
Based on this fact it seems unlikely to be able to construct an aggregation algorithm for calculating θagg without inclusion of the atmospheric forcing conditions. This means that it will be difficult to construct a simple formula
for calculating area-averaged transpiration, if it is possible at all.
Received May 3, 2001; revised May 31, 2002; accepted June 3, 2002 相似文献
20.
Temperature thresholds and crop production: a review 总被引：2，自引：0，他引：2
Qunying Luo 《Climatic change》2011,109(3-4):583-598
Temperature thresholds for a range of crops from cereal crops to horticultural crops and to legum crops were identified through an extensive literature review. Identification of temperature thresholds provides a basis for quantifying the probability of exceeding temperature thresholds which is a very important aspect of climate change risk assessment. The effects of extreme temperatures on yield and yield components were then reviewed and summarised. Through these processes, critical phenophases were defined based on the sensitivity of crop yield and/or yield components to extreme high temperatures which were imposed on various phenophases. Information on the direction and degree of the impact of extreme temperature on yield/yield components can contribute to the improvement of crop models in which the effects of extreme temperature on crop production have not been adequately represented at this stage. Identification of critical phenophases at which crops yield and/or other economic characteristics are sensitive to extreme temperatures will help scoping appropriate adaptation options. 相似文献