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1.
Since the World War II, many economies have transitioned from an agrarian, biomass-based to an industrial, minerals-based metabolic regime. Since 1950, world population grew by factor 2.7 and global material consumption by factor 3.7–71 Gigatonnes per year in 2010. The expansion of the resource base required by human societies is associated with growing pressure on the environment and infringement on the habitats of other species. In order to achieve a sustainability transition, we require a better understanding of the currently ongoing metabolic transition and its potential inertia. In this article, we present a long-term global material flow dataset covering material extraction, trade, and consumption of 177 individual countries between 1950 and 2010. We trace patterns and trends in material flows for six major geographic and economic country groupings and world regions (Western Industrial, the (Former) Soviet Union and its allies, Asia, the Middle East and Northern Africa, Latin America and the Caribbean, and Sub-Saharan Africa) as well as their contribution to the emergence of a global metabolic profile during a period of rapid industrialization and globalization. Global average material use increased from 5.0 to 10.3 tons per capita and year (t/cap/a) between 1950 and 2010. Regional metabolic rates range from 4.5 t/cap/a in Sub-Saharan Africa to 14.8 t/cap/a in the Western Industrial grouping. While we can observe a stabilization of the industrial metabolic profile composed of relatively equal shares of biomass, fossil energy carriers, and construction minerals, we note differences in the degree to which other regions are gravitating toward a similar form of material use. Since 2000, Asia has overtaken the Western Industrial grouping in terms of its share in global resource use although not in terms of its per capita material consumption. We find that at a sub-global level, the roles of the world regions have changed. There are, however, no signs yet that this will lead to stabilization or even a reduction of global resource use.  相似文献   

2.
What drives national adaptation? A global assessment   总被引:1,自引:1,他引:0  
That the climate is changing and societies will have to adapt is now unequivocal, with adaptation becoming a core focus of climate policy. Our understanding of the challenges, needs, and opportunities for climate change adaptation has advanced significantly in recent years yet remains limited. Research has identified and theorized key determinants of adaptive capacity and barriers to adaptation, and more recently begun to track adaptation in practice. Despite this, there is negligible research investigating whether and indeed if adaptive capacity is translating into actual adaptation action. Here we test whether theorized determinants of adaptive capacity are associated with adaptation policy outcomes at the national level for 117 nations. We show that institutional capacity, in particular measures of good governance, are the strongest predictors of national adaptation policy. Adaptation at the national level is limited in countries with poor governance, and in the absence of good governance other presumed determinants of adaptive capacity show limited effect on adaptation. Our results highlight the critical importance of institutional good governance as a prerequisite for national adaptation. Other elements of theorized adaptive capacity are unlikely to be sufficient, effective, or present at the national level where national institutions and governance are poor.  相似文献   

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5.
Dai  Aiguo 《Climate Dynamics》2021,56(11):4027-4049

Global hydroclimatic changes from 1950 to 2018 are analyzed using updated data of land precipitation, streamflow, and an improved form of the Palmer Drought Severity Index. The historical changes are then compared with climate model-simulated response to external forcing to determine how much of the recent change is forced response. It is found that precipitation has increased from 1950 to 2018 over mid-high latitude Eurasia, most North America, Southeast South America, and Northwest Australia, while it has decreased over most Africa, eastern Australia, the Mediterranean region, the Middle East, and parts of East Asia, central South America, and the Pacific coasts of Canada. Streamflow records largely confirm these precipitation changes. The wetting trend over Northwest Australia and Southeast South America is most pronounced in austral summer while the drying over Africa and wetting trend over mid-high latitude Eurasia are seen in all seasons. Coupled with the drying caused by rising surface temperatures, these precipitation changes have greatly increased the risk of drought over Africa, southern Europe, East Asia, eastern Australia, Northwest Canada, and southern Brazil. Global land precipitation and continental freshwater discharge show large interannual and inter-decadal variations, with negative anomalies during El Niño and following major volcanic eruptions in 1963, 1982, and 1991; whereas their decadal variations are correlated with the Interdecadal Pacific Oscillation (IPO) with IPO’s warm phase associated with low land precipitation and continental discharge. The IPO and Atlantic multidecadal variability also dominate multidecadal variations in land aridity, accounting for 90 % of the multidecadal variance. CMIP5 multi-model ensemble mean shows decreased precipitation and runoff and increased risk of drought during 1950–2018 over Southwest North America, Central America, northern and central South America (including the Amazon), southern and West Africa, the Mediterranean region, and Southeast Asia; while the northern mid-high latitudes, Southeast South America, and Northwest Australia see increased precipitation and runoff. The consistent spatial patterns between the observed changes and the model-simulated response suggest that many of the observed drying and wetting trends since 1950 may have resulted at least partly from historical external forcing. However, the drying over Southeast Asia and wetting over Northwest Australia are absent in the 21st century projections.

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6.
In the recent climate change negotiations it was declared that the increase in global temperature should be kept below 2°C by 2100, relative to pre-industrial levels. China's CO2 emissions from energy and cement processes already account for nearly 24% of global emissions, a trend that is expected to keep increasing. Thus the role of China in global GHG mitigation is crucial. A scenario analysis of China's CO2 emissions is presented here and the feasibility of China reaching a low-carbon scenario is discussed. The results suggest that recent and continued technological progress will make it possible for China to limit its CO2 emissions and for these emissions to peak before 2025 and therefore that the global 2°C target can be achieved.

Policy relevance

In signing the Copenhagen Accord, China agreed to the global 2°C target. Results from this article could be used to justify low-carbon development policies and negotiations. While many still doubt the feasibility of a low-carbon pathway to support the global 2°C target, the results suggest that such a pathway can be realistically achieved. This conclusion should increase confidence and guide the policy framework further to make possible China's low-carbon development. Related policies and measures, such as renewable energy development, energy efficiency, economic structure optimization, technology innovation, low-carbon investment, and carbon capture and storage (CCS) development, should be further enhanced. Furthermore, China can play a larger role in the international negotiations process. In the global context, the 2°C target could be reaffirmed and a global regime on an emissions mitigation protocol could be framed with countries’ emissions target up to 2050.  相似文献   

7.
Although many economic studies suggest that China would reap significant benefits from participating in a global cap-and-trade regime, China has consistently refused to participate in international negotiations on this issue. Understanding China's underlying concerns is a key to explaining why China has not embraced an international greenhouse gas emissions trading scheme. This is explored as a potential basis for including China in future negotiations and schemes. This issue is considered from the following perspectives that impact upon China: (a) fairness: how do developing countries perceive emissions caps? (b) why have China and India been sceptical about international emissions trading? (c) what would China's political perceptions be of an inflow of CDM investment in comparison with the exports of emissions permits to the USA? (d) what are the implications of ‘lock in’ to an emissions cap, particularly when no rules and principles exist for setting emissions targets for post-2012? (e) the complex question of establishing future emissions caps for developing countries.  相似文献   

8.
Résumé Une étude théorique permet d'estimer les sommes journalières soit du rayonnement global tombant sur un récepteur plan et horizontal, soit du rayonnement sphérique ou circumglobal tombant sur une sphère. Ces deux sommes dépendent fortement des conditions atmosphèriques: atmosphère pure, brume, humidité et nébulosité, ainsi que de la latitude géographique, de la déclinaison du soleil et de l'albédo du sol. On montre qu'il est quand-même possible de trouver une relation du deuxième ou troisième degré entre les deux types de mesures où les coefficients ne dépendent que de la différence – entre latitude et déclinaison et de l'albédo du sol. Cette relation est valable dans les basses latitudes <30° avec une faible dispersion des valeurs journalières; dans les latitudes plus élevées sa validité semble limitée au semestre estival.
Summary The daily totals of radiation falling on a horizontal receiver as well as on a spherical one are calculated by theoretical approach. Both types of values change very much with atmospherical conditions, such as pure atmosphere, haze and humidity of the atmosphere and cloudiness and furthermore with the geographical latitude, the declination of sun and finally with the albedo of the ground. It is demonstrated that it is nevertheless possible to establish a relation of second or third order between both these types of values. The coefficients are function only of –, the difference between latitude and declination and of the albedo . This relation is valid in low latitudes <30° for daily totals; in higher latitudes its validity is limited to days of the summer period.

Zusammenfassung Auf theoretischem Wege werden die Tagessummen sowohl der auf einen horizontalen Empfänger fallenden Globalstrahlung von Sonne und Himmel als auch der auf eine Kugel fallenden Zirkumglobalstrahlung ermittelt. Beide Werte hängen sehr stark von den atmosphärischen Verhältnissen, wie Reinheit der Atmosphäre, Dunst, Feuchtigkeit und Bewölkung, sowie von der geographischen Breite, der Deklination der Sonne und der Albedo der Bodenoberfläche ab. Es wird nun gezeigt, daß es trotzdem möglich ist, eine Beziehung zweiten oder dritten Grades zwischen den beiden Arten von Tagessummen herzuleiten, in der die Koeffizienten nur von der Differenz – zwischen geographischer Breite und Deklination der Sonne einerseits und der Albedo andererseits abhängen. Diese Beziehung gilt in niederen Breiten <30° für alle Einzelwerte, in höheren Breiten nur im Sommerhalbjahr.


Avec 8 Figures  相似文献   

9.
Guojun Gu  Robert F. Adler 《Climate Dynamics》2013,40(11-12):3009-3022
This study explores how global precipitation and tropospheric water vapor content vary on the interdecadal/long-term time scale during past three decades (1988–2010 for water vapor), in particular to what extent the spatial structures of their variations relate to changes in surface temperature. EOF analyses of satellite-based products indicate that the first two modes of global precipitation and columnar water vapor content anomalies are in general related to the El Niño-Southern oscillation. The spatial patterns of their third modes resemble the corresponding linear fits/trends estimated at each grid point, which roughly represent the interdecadal/long-term changes happening during the same time period. Global mean sea surface temperature (SST) and land surface temperature have increased during the past three decades. However, the water vapor and precipitation patterns of change do not reflect the pattern of warming, in particular in the tropical Pacific basin. Therefore, other mechanisms in addition to global warming likely exist to account for the spatial structures of global precipitation changes during this time period. An EOF analysis of longer-record (1949–2010) SST anomalies within the Pacific basin (60oN–60oS) indicates the existence of a strong climate regime shift around 1998/1999, which might be associated with the Pacific decadal variability (PDV) as suggested in past studies. Analyses indicate that the observed linear changes/trends in both precipitation and tropospheric water vapor during 1988–2010 seem to result from a combined impact of global mean surface warming and the PDV shift. In particular, in the tropical central-eastern Pacific, a band of increases along the equator in both precipitation and water vapor sandwiched by strong decreases south and north of it are likely caused by the opposite effects from global-mean surface warming and PDV-related, La Niña-like cooling in the tropical central-eastern Pacific. This narrow band of precipitation increase could also be considered an evidence for the influence of global mean surface warming.  相似文献   

10.
The global use of and pressure on land resources will continue to rise in tandem with the predicted rise in global population and food demand. Addressing unavoidable trade-offs between satisfying human needs and biodiversity conservation for future generations is of paramount importance when tackling the global environmental challenges of land use. Food consumption patterns are inextricably linked to land-use and land-use changes. The domestic supply and final use of food by humans and feed by animals within the borders of a country have environmental impacts overseas. Countries like Denmark, with considerably high livestock production, import “virtual” land needed to produce cereals and other fodder crops. Denmark's high meat and dairy consumption and trade levels make it a compelling case for this study. The overarching question is: how much land is required to support food and feed consumption in Denmark? This paper assesses the global cropland footprint of Danish food and feed supply from 2000 to 2013 using a consumption-based physical accounting approach. In addition to domestic croplands for local food and supply, we estimate the hectares of cropland displaced in other countries to satisfy Danish demand for food and feed in this period. Secondly, we calculate Denmark's global cropland requirements for the supply of specific livestock products, namely; pork, eggs, beef, milk, and mutton. Globally, animals provide a third of the protein in human diets and agricultural GDP. The total global cropland footprint of Danish food and feed supply decreased by 18% from 1568 kha in 2000 to 1282 kha in 2013 because of a reduction in the consumption of ruminant livestock products. A high share of this reduction can be attributed to increased local self-sufficiency in feed supply as opposed to rising food imports. The share of cropland used for feed in total cropland declined by 5% whereas the share of cropland used for food increased from 28% in 2000 to 32% by 2013. Our findings suggest that reducing domestic meat consumption coupled with local self-sufficiency policies for both food and feed supply could be a means of lowering ecological degradation in exporting countries.  相似文献   

11.
The global summer monsoon precipitation (GSMP) provides a fundamental measure for changes in the annual cycle of the climate system and hydroclimate. We investigate mechanisms governing decadal-centennial variations of the GSMP over the past millennium with a coupled climate model’s (ECHO-G) simulation forced by solar-volcanic (SV) radiative forcing and greenhouse gases (GHG) forcing. We show that the leading mode of GSMP is a forced response to external forcing on centennial time scale with a globally uniform change of precipitation across all monsoon regions, whereas the second mode represents internal variability on multi-decadal time scale with regional characteristics. The total amount of GSMP varies in phase with the global mean temperature, indicating that global warming is accompanied by amplification of the annual cycle of the climate system. The northern hemisphere summer monsoon precipitation (NHSMP) responds to GHG forcing more sensitively, while the southern hemisphere summer monsoon precipitation (SHSMP) responds to the SV radiative forcing more sensitively. The NHSMP is enhanced by increased NH land–ocean thermal contrast and NH-minus-SH thermal contrast. On the other hand, the SHSMP is strengthened by enhanced SH subtropical highs and the east–west mass contrast between Southeast Pacific and tropical Indian Ocean. The strength of the GSMP is determined by the factors controlling both the NHSMP and SHSMP. Intensification of GSMP is associated with (a) increased global land–ocean thermal contrast, (b) reinforced east–west mass contrast between Southeast Pacific and tropical Indian Ocean, and (c) enhanced circumglobal SH subtropical highs. The physical mechanisms revealed here will add understanding of future change of the global monsoon.  相似文献   

12.
13.
The radiative impacts of the stratosphere in global warming simulations are investigated using abrupt CO2 quadrupling experiments of the Coupled Model Inter-comparison Project phase 5 (CMIP5), with a focus on stratospheric temperature and water vapor. It is found that the stratospheric temperature change has a robust bullhorn-like zonal-mean pattern due to a strengthening of the stratospheric overturning circulation. This temperature change modifies the zonal mean top-of-the-atmosphere energy balance, but the compensation of the regional effects leads to an insignificant global-mean radiative feedback (?0.02 ± 0.04 W m?2 K?1). The stratospheric water vapor concentration generally increases, which leads to a weak positive global-mean radiative feedback (0.02 ± 0.01 W m?2 K?1). The stratospheric moistening is related to mixing of elevated upper-tropospheric humidity, and, to a lesser extent, to change in tropical tropopause temperature. Our results indicate that the strength of the stratospheric water vapor feedback is noticeably larger in high-top models than in low-top ones. The results here indicate that although its radiative impact as a forcing adjustment is significant, the stratosphere makes a minor contribution to the overall climate feedback in CMIP5 models.  相似文献   

14.
全球季风   总被引:1,自引:0,他引:1       下载免费PDF全文
<正>全球季风是21世纪才提出来的新概念[1-4]。现代气候学的全球季风与经典气候学的季风有3点不同:1)现代气候学把季风视为全球现象,而不像经典气候学那样把季风视为局地现象、认为季风是二级环流(西风环流为一级环流);2)现代气候学认为季风形成的机制是随季  相似文献   

15.
韩起 《气象科技》1990,(5):39-44
一、综述世界气候是一个动力体系,它受所有时间尺度的自然变化的制约和人类活动的影响.我们知道,在过去百万年间,在冰河期和间冰期之间,仅仅由于地球吸收的太阳辐射的微小变化,便使气候发生了变化.因此,人类活动引起的未来气候变化的预报问题涉及到对自然变化的理解和预报.世界气候研究计划(WCRP)就是针对这两个问题而制定的.  相似文献   

16.
Widely distributed proxy records indicate that the Medieval Climate Anomaly (MCA; ~900–1350 AD) was characterized by coherent shifts in large-scale Northern Hemisphere atmospheric circulation patterns. Although cooler sea surface temperatures in the central and eastern equatorial Pacific can explain some aspects of medieval circulation changes, they are not sufficient to account for other notable features, including widespread aridity through the Eurasian sub-tropics, stronger winter westerlies across the North Atlantic and Western Europe, and shifts in monsoon rainfall patterns across Africa and South Asia. We present results from a full-physics coupled climate model showing that a slight warming of the tropical Indian and western Pacific Oceans relative to the other tropical ocean basins can induce a broad range of the medieval circulation and climate changes indicated by proxy data, including many of those not explained by a cooler tropical Pacific alone. Important aspects of the results resemble those from previous simulations examining the climatic response to the rapid Indian Ocean warming during the late twentieth century, and to results from climate warming simulations—especially in indicating an expansion of the Northern Hemisphere Hadley circulation. Notably, the pattern of tropical Indo-Pacific sea surface temperature (SST) change responsible for producing the proxy-model similarity in our results agrees well with MCA-LIA SST differences obtained in a recent proxy-based climate field reconstruction. Though much remains unclear, our results indicate that the MCA was characterized by an enhanced zonal Indo-Pacific SST gradient with resulting changes in Northern Hemisphere tropical and extra-tropical circulation patterns and hydroclimate regimes, linkages that may explain the coherent regional climate shifts indicated by proxy records from across the planet. The findings provide new perspectives on the nature and possible causes of the MCA—a remarkable, yet incompletely understood episode of Late Holocene climatic change.  相似文献   

17.
Current international efforts to reduce greenhouse gas emissions and limit human-induced global-mean near-surface temperature increases to 2°C, relative to the pre-industrial era, are intended to avoid possibly significant and dangerous impacts to physical, biological, and socio-economic systems. However, it is unknown how these various systems will respond to such a temperature increase because their relevant spatial scales are much different than those represented by numerical global climate models—the standard tool for climate change studies. This deficiency can be addressed by using higher-resolution regional climate models, but at great computational expense. The research presented here seeks to determine how a 2°C global-mean temperature increase might change the frequency of seasonal temperature extremes, both in the United States and around the globe, without necessarily resorting to these computationally-intensive model experiments. Results indicate that in many locations the regional temperature increases that accompany a 2°C increase in global mean temperatures are significantly larger than the interannual-to-decadal variations in seasonal-mean temperatures; in these locations a 2°C global mean temperature increase results in seasonal-mean temperatures that consistently exceed the most extreme values experienced during the second half of the 20th Century. Further, results indicate that many tropical regions, despite having relatively modest overall temperature increases, will have the most substantial increase in number of hot extremes. These results highlight that extremes very well could become the norm, even given the 2°C temperature increase target.  相似文献   

18.
The global monsoon (GM) is a defining feature of the annual variation of Earth’s climate system. Quantifying and understanding the present-day monsoon precipitation change are crucial for prediction of its future and reflection of its past. Here we show that regional monsoons are coordinated not only by external solar forcing but also by internal feedback processes such as El Ni?o-Southern Oscillation (ENSO). From one monsoon year (May to the next April) to the next, most continental monsoon regions, separated by vast areas of arid trade winds and deserts, vary in a cohesive manner driven by ENSO. The ENSO has tighter regulation on the northern hemisphere summer monsoon (NHSM) than on the southern hemisphere summer monsoon (SHSM). More notably, the GM precipitation (GMP) has intensified over the past three decades mainly due to the significant upward trend in NHSM. The intensification of the GMP originates primarily from an enhanced east–west thermal contrast in the Pacific Ocean, which is coupled with a rising pressure in the subtropical eastern Pacific and decreasing pressure over the Indo-Pacific warm pool. While this mechanism tends to amplify both the NHSM and SHSM, the stronger (weaker) warming trend in the NH (SH) creates a hemispheric thermal contrast, which favors intensification of the NHSM but weakens the SHSM. The enhanced Pacific zonal thermal contrast is largely a result of natural variability, whilst the enhanced hemispherical thermal contrast is likely due to anthropogenic forcing. We found that the enhanced global summer monsoon not only amplifies the annual cycle of tropical climate but also promotes directly a “wet-gets-wetter” trend pattern and indirectly a “dry-gets-drier” trend pattern through coupling with deserts and trade winds. The mechanisms recognized in this study suggest a way forward for understanding past and future changes of the GM in terms of its driven mechanisms.  相似文献   

19.
A key climate policy issue and debate is the future trajectory of emissions of carbon dioxide of countries, their peaking dates, and rates of decline after peaking. This article analyses China’s emissions trajectory in terms of global historical trends distinguishing between industry, infrastructure, and urbanization. Growth of emissions from industrialization and infrastructure development has stabilized in 2014 with saturation levels being reached, while the process of urbanization continues with the shift of the economy to the services sector, with reduced energy use, and this is a global trend. The future trajectory of emissions will be shaped largely by growth of transport and building-related services which directly impact on and are shaped by middle-class levels of well-being. These are areas where convergence with levels of services in other urbanized countries is an important element of national policy. This global trend has not been adequately taken into account in modelling and macroeconomic analysis which ignore social processes. The article concludes that China’s 13th Five Year Plan (2016–2020) seeks to achieve a ‘moderately well-off society’ while putting a cap on total energy demand by modifying the drivers of consumption emissions compared with countries that urbanized earlier. The adoption of a public policy priority of dense mixed-use urban form, public transport, energy efficiency to enable energy system reform, and digital economy could be a model for others.

Policy relevance

The article redefines climate change in terms of social processes as urban form and notions of well-being lock-in increasing levels of future emissions of carbon dioxide. There are implications for research in assessing how best drivers of emissions can be modified without affecting well-being, including renewable and digital technologies and human behaviours that drive patterns of natural resource use as well as the identification of leverage points. There are also broader implications for replacing the development cooperation model of global climate governance to focus on new values recognizing interdependencies for sharing responsibility as well as prosperity.  相似文献   


20.
史国宁 《气象》1979,5(1):13-16
一、第一次全球试验计划产生的背景—— 世界天气监视网和全球大气研究计划 进入20世纪60年代,由于高速电子计算机的发展,数值预报方法在日常天气预报业务中有了较广泛的应用。为了进一步提高数值预报能力,延长预报时效,一个首要的条件是必需获得全球范围的观测资料;另一方面由于气象卫星等先进的观测手段的出现,进行全球联合观测的可能性也已具备。在这种形势下,在气象领域中两个空前规模的国际合作计划就应运而生了。其一是世界气象组织于1962年组织的世界天气监视网计划,英文缩写为WWW;另一称为全球大气研究计划,英文缩写为GARP。它是1965年在世界气象组织和国际科协理事会共同筹划下产生  相似文献   

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