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1.
We propose linear response functions to separately estimate the sea-level contributions of thermal expansion and solid ice discharge from Greenland and Antarctica. The response function formalism introduces a time-dependence which allows for future rates of sea-level rise to be influenced by past climate variations. We find that this time-dependence is of the same functional type, R(t) ～ t α, for each of the three subsystems considered here. The validity of the approach is assessed by comparing the sea-level estimates obtained via the response functions to projections from comprehensive models. The pure vertical diffusion case in one dimension, corresponding to α = ?0.5, is a valid approximation for thermal expansion within the ocean up to the middle of the twenty first century for all Representative Concentration Pathways. The approximation is significantly improved for α = ? 0.7. For the solid ice discharge from Greenland we find an optimal value of α = ?0.7. Different from earlier studies we conclude that solid ice discharge from Greenland due to dynamic thinning is bounded by 0.42 m sea-level equivalent. Ice discharge induced by surface warming on Antarctica is best captured by a positive value of α = 0.1 which reflects the fact that ice loss increases with the cumulative amount of heat available for softening the ice in our model. 相似文献
2.
Stéphane Hallegatte 《Global Environmental Change》2009,19(2):240-247
Many decisions concerning long-lived investments already need to take into account climate change. But doing so is not easy for at least two reasons. First, due to the rate of climate change, new infrastructure will have to be able to cope with a large range of changing climate conditions, which will make design more difficult and construction more expensive. Second, uncertainty in future climate makes it impossible to directly use the output of a single climate model as an input for infrastructure design, and there are good reasons to think that the needed climate information will not be available soon. Instead of optimizing based on the climate conditions projected by models, therefore, future infrastructure should be made more robust to possible changes in climate conditions. This aim implies that users of climate information must also change their practices and decision-making frameworks, for instance by adapting the uncertainty-management methods they currently apply to exchange rates or R&D outcomes. Five methods are examined: (i) selecting “no-regret” strategies that yield benefits even in absence of climate change; (ii) favouring reversible and flexible options; (iii) buying “safety margins” in new investments; (iv) promoting soft adaptation strategies, including long-term prospective; and (v) reducing decision time horizons. Moreover, it is essential to consider both negative and positive side-effects and externalities of adaptation measures. Adaptation–mitigation interactions also call for integrated design and assessment of adaptation and mitigation policies, which are often developed by distinct communities. 相似文献
3.
Maciej Sadowski 《Climatic change》2008,90(4):443-451
Adopted by COP 10 (Dec 1/CP.10) and approved by the MOP1, the Buenos Aires programme of adaptation and response measures opens
doors to intensify preparations for expected climate change. By this decision the COP, requested the SBSTA to develop a structured
5-year programme of work of the SBSTA on the scientific, technical and socio-economic aspects of impacts of, and vulnerability
and adaptation to, climate change. Consequently, the COP, by its decision 2/CP.11, adopted the “Five-year programme of work
of the Subsidiary Body for Scientific and Technological Advice on impacts, vulnerability and adaptation to climate change”
Finally during COP12 this programme was approved as “Nairobi Work Programme on impacts, vulnerability and adaptation to climate
change”. This programme has fundamental significance not only for developing countries, but also for industrialized nations
in which some sectors of the or social life are particularly vulnerable to climate change, specifically, inter alia EIT countries and new EU Member States. Further development of this adaptation programme economy should contain steps that
provide optimum economic and social effectiveness, risk management, identification of vulnerable sectors and gaps in knowledge,
preparation of a list of policy options, including an analysis of cost effectiveness, selection of the most effective policies,
and a preparedness implementation plan. In Poland the preliminary adaptation programme covered agriculture, water management,
and coastal zone management. For the time being, gaps in knowledge and preparedness measures have been identified. An estimation
of possible impact on these areas was based on chosen GCMs, and sea level rise IPCC scenarios. In conclusion, it was stated
that the results achieved should be seen as a first step forward and a more comprehensive study is necessary to update the
results and cover other sectors of the economy, such as health protection, spatial planning, ecosystems and forestry, and
to develop specific guidelines and recommendations for policy-makers. 相似文献
4.
Size segregated sampling of aerosol particles at the coal-fired power station Šoštanj, Slovenia was performed by a newly developed
system. In addition, simultaneous sampling of particles was performed at two locations, Velenje and Veliki vrh, chosen on
the basis of long term monitoring of SO2 in the influential area of power plant. The signature of the power plant (e.g. characteristic size distributions of some
typical trace elements) was identified. For elements, like As, Mo, Cd and Ga, which are typical for coal combustion, the highest
concentrations were observed in the size range between 1 and 4 μm. For Se and sometimes for Ga two modes were identified,
first between 0.1 and 0.5 μm and second between 1 and 4 μm. Ratios between the average concentrations of selected elements
in fine and coarse particles collected at Veliki vrh (the most influenced location) and Velenje (usually not influenced by
the thermo power station) were significantly higher than 1 in the case of Mo and Se for coarse and fine size range, while
for As the ratio was higher than 1 for the coarse fraction. Consequently, Mo, Se and As were found as the most important tracers
for the emissions from the investigated source. On the basis of the ratios between the concentrations of elements measured
in particles at low and high SO2 concentrations at Veliki vrh, Cd was shown to be a typical tracer as well. Our results definitely showed that size segregated
measurements of particles at the source and in the influenced area give more precise information on the influence of source
to the surrounding region. It was found that patterns of size distributions for typical trace elements observed at the source
are found also in the influenced area, i.e. Veliki vrh. 相似文献
5.
The link between the sea-ice cover of the Amundsen Gulf and the overlying atmospheric boundary layer was explored on a weekly
timestep from winter to summer 2008. The total sea-ice cover was around 97% (3% leads) from 7 January to 21 April. From 28
April to 12 May, the total sea-ice cover approached 100%. From May 19, the total sea-ice declined rapidly to its July minimum
of 3%. During the winter, a turbulent internal boundary layer (IBL), attributed to the upward flux of sensible heat (mean = 46 W m−2), was present in most of the mean daily potential temperature profiles. The mean latent heat flux was 1.7 Wm−2. A turbulent IBL was also present in most of the mean daily profiles for early spring. Surface fluxes were not estimated.
During late spring and early summer, a stable IBL, attributed to the downward flux of sensible heat (mean = −19 W m−2), was present in most of the potential temperature profiles. Both downward and upward fluxes of latent heat occurred in this
period (means = −3.3 and 1.1 W m−2). The sensible heat flux estimates are consistent with the results of others; however, the latent heat flux estimates may
be too small due to condensation/deposition within the IBL. The unconsolidated nature of the pack ice in the Amundsen Gulf,
and the low sea-surface temperatures following break-up, were critical factors controlling the presence and type of IBL. 相似文献
6.
Analysis of human adaptation to climate change should be based on realistic models of adaptive behaviour at the level of organisations and individuals. The paper sets out a framework for analysing adaptation to the direct and indirect impacts of climate change in business organisations with new evidence presented from empirical research into adaptation in nine case-study companies. It argues that adaptation to climate change has many similarities with processes of organisational learning. The paper suggests that business organisations face a number of obstacles in learning how to adapt to climate change impacts, especially in relation to the weakness and ambiguity of signals about climate change and the uncertainty about benefits flowing from adaptation measures. Organisations rarely adapt ‘autonomously’, since their adaptive behaviour is influenced by policy and market conditions, and draws on resources external to the organisation. The paper identifies four adaptation strategies that pattern organisational adaptive behaviour. 相似文献
7.
To respond to climate impact, poor agricultural households in less developed regions rely on different types of assets that define their overall adaptive capacity (AC). However not all assets build capacity equally. In this study we argue that building AC requires a combination of interventions that address not only climate-related risks (specific capacity) but also the structural deficits (e.g., lack of income, education, health, political power) (generic capacity) that shape vulnerability. Focusing on rainfed agriculture in NE Brazil, we investigate how households leverage and combine generic and specific capacities to reduce vulnerability. Particularly we explore: 1) the relative importance of different kinds of capacity in shaping vulnerability on these households and 2) how the level of generic capacities (particularly as a result of Brazil’s anti-poverty program Bolsa Família) influences the adoption of specific ones. We find that both kinds of capacity matter, as relatively higher levels of generic capacity (in terms of income in general, and climate-neutral income specifically) are associated with higher levels of specific capacity (irrigation). In addition we find that while Bolsa Família has been positive in increasing income, it has not been sufficient to manage the risk of food insecurity during drought events, suggesting a 'poverty trap' in which families are constantly coping with drought but failing to overcome the conditions that make them vulnerable. Our findings indicate that in order to decrease climate vulnerability of poor agricultural households, development interventions, such as anti-poverty programs, have to go beyond cash transfer and should incorporate risk management policies that enhance synergies between generic and specific capacities. 相似文献
8.
The paper presents a coupled chemical-radiative one-dimensional model which is used to assess the steady-state and time-dependent composition and temperature changes in relation to the release in the atmosphere of chemicals such as CO2, N2O, CH4, NO
x
and chlorofluorocarbons.The model indicates that a doubling in CO2 leads to an increase in temperature of 12.7 K near the stratopause and to an increase in total ozone of 3.3% with a local enhancement of 17% at 40 km altitude. Additional release of N2O leads to an ozone reduction in the middle stratosphere. The reduction in the ozone column is predicted to be equal to 8.8% when the amount of N2O is doubled. The chemical effect of CH4 on ozone is particularly important in the troposphere. A doubling in the mixing ratio of this gas enhances the O3 concentration by 11% at 5 km. The predicted increase of the ozone column is equal to 1.4%. A constant emission of CFCl3 (230 kT/yr) and CF2Cl2 (300 kT/yr) leads to a steady-state reduction in the ozone column of 1.9% compared to the present-day situation. The effect of some uncertainties in the chemical scheme as well as the impact of a high chlorine perturbation are briefly discussed.Finally the results of a time dependent calculation assuming a realistic scenario for the emission of chemical species are presented and analyzed. 相似文献
9.
Godefroy Grosjean Sabine Fuss Nicolas Koch Benjamin L. Bodirsky Stéphane De Cara William Acworth 《Climate Policy》2018,18(2):151-169
Although agriculture could contribute substantially to European emission reductions, its mitigation potential lies untapped and dormant. Market-based instruments could be pivotal in incentivizing cost-effective abatement. However, sector specificities in transaction costs, leakage risks and distributional impacts impede its implementation. The significance of such barriers critically hinges on the dimensions of policy design. This article synthesizes the work on emissions pricing in agriculture together with the literature on the design of market-based instruments. To structure the discussion, an options space is suggested to map policy options, focusing on three key dimensions of policy design. More specifically, it examines the role of policy coverage, instruments and transfers to farmers in overcoming the barriers. First, the results show that a significant proportion of agricultural emissions and mitigation potential could be covered by a policy targeting large farms and few emission sources, thereby reducing transaction costs. Second, whether an instrument is voluntary or mandatory influences distributional outcomes and leakage. Voluntary instruments can mitigate distributional concerns and leakage risks but can lead to subsidy lock-in and carbon price distortion. Third, the impact on transfers resulting from the interaction of the Common Agricultural Policy (CAP) with emissions pricing will play a key role in shaping political feasibility and has so far been underappreciated.
POLICY RELEVANCE
Following the 2015 Paris Agreement, European climate policy is at a crossroads. Achieving cost-effectively the 2030 and 2050 European targets requires all sectors to reduce their emissions. Yet, the cornerstone of European climate policy, the European Union Emissions Trading System (EU ETS), covers only about half of European emissions. Major sectors have been so far largely exempted from carbon pricing, in particular transport and agriculture. While transport has been increasingly under the spotlight as a possible candidate for an EU ETS sectoral expansion, policy discussions on pricing agricultural emissions have been virtually absent. This article attempts to fill this gap by investigating options for market-based instruments to reduce agricultural emissions while taking barriers to implementation into account. 相似文献
10.
Abstract Economic studies suggest that market leakage rates of greenhouse gas abatement can reach the two-digit percentage range. Although the Marrakesh Accords require Clean Development Mechanism (CDM) projects to account for leakage, most projects neglect market leakage. Insufficient leakage accounting is facilitated by a lack of applicable methods regarding the quantification and attribution of project-related leakage effects. This article proposes a method for attributing CDM-related market leakage effects to individual projects. To this purpose, alternative attribution methods are analysed. We find that project-specific approaches fail to take account of market leakage effects. Consequently, we propose to estimate aggregate market leakage effects and attribute them proportionally to individual projects. We suggest that predetermined commodity-specific leakage factors are applied by project developers to any emission reductions that are associated with a project's leakage-relevant demand or supply changes. This approach is conservative, equitable, incentive-compatible and applicable at manageable costs. 相似文献
11.
12.
Prof. C. L. Godske 《Theoretical and Applied Climatology》1966,14(3-4):269-279
Summary After introductory remarks on the manyfold difficulties in climatological work the author attempts a more precise definition of Climatology, which is often called the science of the average weather, as the science of the multivariate distributions of meteorological elements with time and space. A climatological study has to be made in various stemps, each of which has to keep constant a minor number of variables than the preceding one. In the selection of the mathematical models one has to pay attention to two principles, which often oppose each other: simplicity and generality. The goodness of fit of the model has to be proved. In proceeding to higher levels of the climatological analysis. Studies should be undertaken by means of some stations with long series of data with regard to the necessary length of the period of observations. The author is convinced that all these costly investigations would be of utmos value for humanity.
With 2 Figures
Lecture given at the IV. Session of the Commission for Climatology of WMO, August 18, 1965 in Stockholm. 相似文献
Zusammenfassung Es werden zunächst Beispiele für die mannigfachen Schwierigkeiten der klimatologischen Arbeit angeführt, wie sie z. B. durch unenheitliche Definitionen und Repräsentationsarten, heterogene Beobachtungsreihen, baobachtungslücken u. ä. m. verursacht werden. Dann wird die Definition der Klimatologie als Wissenschaft vom durchschnittlichen Wetter präzisiert als Wissenschaft, die die multivariablen statistischen Verteilungen der meteorologischen Elemente mit Orts- und Zeitkoordinaten zu studieren hat. Eine klimatologische Studie muß mit Teilstudien beginnen, die zunächst einige der Variablen konstant halten; das Resultat dieser Teilstudien muß Wegweiser sein beim Fortschreiten zu höheren Dimensionen. Bei der Auswahl der mathematischen Modelle in allen Stufen ist auf swei Prinzipien Rücksicht zu nehmen, die einander widersprechen können: das Modell soll einfach sein, soll aber doch zu verallgemeinern sein. Die Güte der Anpassung des Modells andie Daten muß geprüft werden, z. B. durch die Methoden der Konfidenzintervalle oder der Subperioden. Beim Fortschreiten zu höheren Modellen sind die Methoden der Analyse von einfachen oder multiplen Zeitreihen zu berücksichtigen. Für die Frage einer hinreichend langen Bearbeitungsperiode sollten Untersuchungen aller Stufen mit einer Anzahl von Schlüsselstationen durchgeführt werden. Der Autor ist der Ansicht, daß sich alle die angeführten kostspieligen Untersuchungen für die Allgemeinheit bezahlt machen werden.
Résumé L'auteur présente tout d'abord quelques exemples des nombreuses difficulté inhérentes à tout travail en climatologie. Ces difficulté proviennent soit dufait que les définitions et les formes de représentation des qu'il y ait des lacunes dans les séries d'observations, soit d'autres causes encore. Il définit ensuite la climatologie comme étant la science du temps moyen et plus particulièrement la science chargée d'étudier la répartition statistique multiple des éléments météorologiques et cela auusi bien dans le temps que dans l'espace. Une recherche en climatologie doit débuter par des études partielles c'est à dire ne laissant, au préalable, varier que quelques éléments du climat, les autres restant constants. Les résultats obtenus lors de ces études partielles indiqueront alors dans quelles directions poursuivre. Lors du choix des modèles mathématiques, il faut tenir compte, à tous les niveaux, de deux principes qui peuvent être contradictoires: Le modèle doit être simple, mais il doit permettre des généralisations. Il faut étudier les possibilités d'adaptation du modèle choisi aux séries de chiffres à étudier en utilisant par exemple des périodes secondaires ou l'intervalle situé entre les limites de confiance. En passant à des modèles de degré supérieur, il est nécessaire de tenir compte des méthodes d'analyse de séries chronologiques simples et multiples. Pour déterminer quelle longueur au moins doit avoir une période d'observations, il faudrait étudier à tous les degrés un contrôle avec un certain nombre de stations typiques. L'auteur pense que toutes ces recherches sont rentables pour la collectivité, même si leur coût est élevé.
With 2 Figures
Lecture given at the IV. Session of the Commission for Climatology of WMO, August 18, 1965 in Stockholm. 相似文献
13.
A. C. Chamberlain 《Boundary-Layer Meteorology》1974,6(3-4):477-486
A vapour of radio-lead (212Pb) has been used to measure the Sherwood number, Sh, of model leaves at various angles of incidence,, to the airstream in a wind tunnel. The results for=0 are compared with Pohlhausen's formula and the results for 0, with Powell's experiments. The local values of Sh on the upwind and downwind sides of discs have been obtained. For leaves in the canopy, Sh was found to be about 25% greater than would be predicted by applying Pohlhausen's equation without correction for orientation. 相似文献
14.
We use a reduced complexity climate model with a three-dimensional ocean component and realistic topography to investigate
the effect of stratification-dependent mixing on the sensitivity of the North Atlantic subpolar gyre (SPG), and the Atlantic
meridional overturning circulation (AMOC), to idealized CO2 increase and peaking scenarios. The vertical diffusivity of the ocean interior is parameterized as κ ∼ N
−α, where N is the local buoyancy frequency. For all parameter values 0 ≤ α ≤ 3, we find the SPG, and subsequently the AMOC, to weaken
in response to increasing CO2 concentrations. The weakening is significantly stronger for α ≥ αcr ≈ 1.5. Depending on the value of α, two separate model states develop. These states remain different after the CO2 concentration is stabilized, and in some cases even after the CO2 concentration has been decreased again to the pre-industrial level. This behaviour is explained by a positive feedback between
stratification and mixing anomalies in the Nordic Seas, causing a persistent weakening of the SPG. 相似文献
15.
Summary PVA-maxima can be a contributor to upward motion; there-fore cloudiness and precipitation can be expected there. This is investigated from several viewpoints: grey shade evaluations of false colour satellite images are done, frequencies of precipitation events for PVA maxima and grey shade intervals are investigated, precipitation amounts within the PVA maxima path are compared to a surroundings and the predictability from the ECMWF model is proved. Several results could be derived: PVA maxima are accompanied by brighter grey shade intervals and a higher precipitation probability than surrounding areas; for the brightest grey shade intervals a probability for precipitation of 60–70% can be stated; the path of the PVA maxima is an area of more precipitation than in the surroundings; ECMWF forecasts are able to predict the PVA maxima and their location very well but tend to underestimate the precipitation amounts on the PVA maxima path.With 9 Figures 相似文献
16.
Carbon sequestration in agricultural soils is frequently promoted as a practical solution for slowing down the rate of increase
of CO2 in the atmosphere. Consequently, there is a need to improve our understanding of how land management practices may affect
the net removal of greenhouse gases (GHG) from the atmosphere. In this paper we examine the role of agriculture in influencing
the GHG budget and briefly discuss the potential for carbon mitigation by agriculture. We also examine the opportunities that
exist for increasing soil C sequestration using management practices such as reduced tillage, reduced frequency of summer
fallowing, introduction of forage crops into crop rotations, conversion of cropland to grassland and nutrient addition via
fertilization. In order to provide information on the impact of such management practices on the net GHG budget we ran simulations
using CENTURY (a C model) and DNDC (a N model) for five locations across Canada, for a 30-yr time period. These simulations
provide information on the potential trade-off between C sequestration and increased N2O emissions. Our model output suggests that conversion of cropland to grassland will result in the largest reduction in net
GHG emissions, while nutrient additions via fertilizers will result in a small increase in GHG emissions. Simulations with
the CENTURY model also indicated that favorable growing conditions during the last 15 yr could account for an increase of
6% in the soil C at a site in Lethbridge, Alberta.
Presented at the International Workshop on Reducing Vulnerability of Agriculture and Forestry to Climate Variability and Climate
Change, Ljubljana, Slovenia, 7–9 October 2002. 相似文献
17.
B. Primault 《Theoretical and Applied Climatology》1992,45(2):139-143
Summary The beginning of tree growth in the spring, denoted by the arrival of a phenophase, varies from year to year. The ambient air temperature is probably the most important factor for vegetation growth in spring. Starting from an initial concept of the beginning of the vegetation period as being seven days with a mean temperature of 5.0 °C or greater, we modify the threshold (going down to 2 °C) and the length of the reaction period (five to nine days). To estimate the effect of these changes on the results at several geographical sites, we calculated the modifications obtained for three weather stations in Switzerland: Zurich (590 m), Einsiedeln (914 m) and Davos (1600 m). To obtain a clear picture of the influence of these changes, we used a frequency of data obtained during the period 1931–1970 (maximum, 90%, 75%, 50%, 25%, 10%, minimum). In conclusion, the lower the threshold of temperature, the earlier the computed start date for growth. Similarly, the shorter the lapse time, the earlier the date produced for the phenophase. Both modifications have no significant influence on the picture of the frequential distribution of the results.With 5 Figures 相似文献
18.
19.
The eastward shift of the Walker Circulation in response to global warming and its relationship to ENSO variability 总被引：1，自引：1，他引：0
Tobias Bayr Dietmar Dommenget Thomas Martin Scott B. Power 《Climate Dynamics》2014,43(9-10):2747-2763
This study investigates the global warming response of the Walker Circulation and the other zonal circulation cells (represented by the zonal stream function), in CMIP3 and CMIP5 climate models. The changes in the mean state are presented as well as the changes in the modes of variability. The mean zonal circulation weakens in the multi model ensembles nearly everywhere along the equator under both the RCP4.5 and SRES A1B scenarios. Over the Pacific the Walker Circulation also shows a significant eastward shift. These changes in the mean circulation are very similar to the leading mode of interannual variability in the tropical zonal circulation cells, which is dominated by El Niño Southern Oscillation variability. During an El Niño event the circulation weakens and the rising branch over the Maritime Continent shifts to the east in comparison to neutral conditions (vice versa for a La Niña event). Two-thirds of the global warming forced trend of the Walker Circulation can be explained by a long-term trend in this interannual variability pattern, i.e. a shift towards more El Niño-like conditions in the multi-model mean under global warming. Further, interannual variability in the zonal circulation exhibits an asymmetry between El Niño and La Niña events. El Niño anomalies are located more to the east compared with La Niña anomalies. Consistent with this asymmetry we find a shift to the east of the dominant mode of variability of zonal stream function under global warming. All these results vary among the individual models, but the multi model ensembles of CMIP3 and CMIP5 show in nearly all aspects very similar results, which underline the robustness of these results. The observed data (ERA Interim reanalysis) from 1979 to 2012 shows a westward shift and strengthening of the Walker Circulation. This is opposite to what the results in the CMIP models reveal. However, 75 % of the trend of the Walker Circulation can again be explained by a shift of the dominant mode of variability, but here towards more La Niña-like conditions. Thus in both climate change projections and observations the long-term trends of the Walker Circulation seem to follow to a large part the pre-existing dominant mode of internal variability. 相似文献
20.
Jill Jäger 《Climatic change》1992,20(2):iii-vii
Jill Jäger was Head of the Climate Programme of the Stockholm Environment Institute during the time that she coordinated the AGGG ad hoc Working Groups and edited the Proceedings of the Second World Climate Conference. She is now Co-Director of the Climate Policy Division of the Wuppertal Institute for Climate, Environment and Energy in Germany. 相似文献