scholarly journals Probabilistic Forecast for Twenty-First-Century Climate Based on Uncertainties in Emissions (Without Policy) and Climate Parameters

2009 ◽  
Vol 22 (19) ◽  
pp. 5175-5204 ◽  
Author(s):  
A. P. Sokolov ◽  
P. H. Stone ◽  
C. E. Forest ◽  
R. Prinn ◽  
M. C. Sarofim ◽  
...  

Abstract The Massachusetts Institute of Technology (MIT) Integrated Global System Model is used to make probabilistic projections of climate change from 1861 to 2100. Since the model’s first projections were published in 2003, substantial improvements have been made to the model, and improved estimates of the probability distributions of uncertain input parameters have become available. The new projections are considerably warmer than the 2003 projections; for example, the median surface warming in 2091–2100 is 5.1°C compared to 2.4°C in the earlier study. Many changes contribute to the stronger warming; among the more important ones are taking into account the cooling in the second half of the twentieth century due to volcanic eruptions for input parameter estimation and a more sophisticated method for projecting gross domestic product (GDP) growth, which eliminated many low-emission scenarios. However, if recently published data, suggesting stronger twentieth-century ocean warming, are used to determine the input climate parameters, the median projected warming at the end of the twenty-first century is only 4.1°C. Nevertheless, all ensembles of the simulations discussed here produce a much smaller probability of warming less than 2.4°C than implied by the lower bound of the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) projected likely range for the A1FI scenario, which has forcing very similar to the median projection in this study. The probability distribution for the surface warming produced by this analysis is more symmetric than the distribution assumed by the IPCC because of a different feedback between the climate and the carbon cycle, resulting from the inclusion in this model of the carbon–nitrogen interaction in the terrestrial ecosystem.

1997 ◽  
Vol 1 (1) ◽  
pp. 51-68
Author(s):  
Harold K. Jacobson

The creation and proliferation of international organizations of various sorts, increasing economic interdependence, the spread of democracy. and the strong leadership played by the United States all worked positively together to facilitate international cooperation during the second half of the twentieth century, overcoming to a great extent the familiar problem of 'cooperation under anarchy. 'But humankind is confronting new challenges as well, arising from the shift in power relations among nation-states and the rise of new issues that call for global. attention. One of the most prominent issues is the protection of environment. It is unclear how easily the formulas that have proved to be so successful in bringing about international cooperation in the twentieth century can be applied to the new challenges. If a series of organised responses to the issue of climate change as shown in the completion and implementation of the Framework Convention on Climate Change (FCCC) is any indication, however, the international. community seems to have successfully begun to confront them. The relative promptness of action taken by the international community. the manner in which the issue is negotiated where the principle of equity was directly addressed, the comprehensiveness of the Treaty's scope, and responsible behaviour of the states of the world, all point to broad optimism about international cooperation in the twenty-first century.


2003 ◽  
Vol 84 (12) ◽  
pp. 1711-1724 ◽  
Author(s):  
Michael C. MacCracken ◽  
Eric J. Barron ◽  
David R. Easterling ◽  
Benjamin S. Felzer ◽  
Thomas R. Karl

In support of the U.S. National Assessment of the Potential Consequences of Climate Variability and Change, climate scenarios were prepared to serve as the basis for evaluating the vulnerability of environmental and societal systems to changes projected for the twenty-first century. Since publication of the results of the assessment at the end of 2000, the National Research Council's report Climate Change Science: An Analysis of Some Key Questions, and the U.S. government's U.S. Climate Action Report—2002 have both relied on the assessment's findings. Because of the importance of these findings, it is important to directly address questions regarding the representativeness and usefulness of the model-based projections on which the findings were based. In particular, criticisms have focused on whether the climate models that were relied upon adequately represented twentieth-century conditions and whether their projections of conditions for the twenty-first century were outliers. Reexamination of the approach used in developing and evaluating the climate scenarios indicates that the results from the two primary climate modeling groups that were relied upon allowed the generation of climate scenarios that span much of the range of possible future climatic conditions projected by the larger set of model simulations, which was compiled for the IPCCs Third Assessment Report. With the set of models showing increasing agreement in their simulations of twentieth-century trends in climate and of projected changes in climate on subcontinental to continental scales, the climate scenarios that were generated seem likely to provide a plausible representation of the types of climatic conditions that could be experienced during the twenty-first century. Warming, reduced snow cover, and more intense heavy precipitation events were projected by all models, suggesting such changes are quite likely. However, significant differences remain in the projection of changes in precipitation and of the regional departures in climate from the larger-scale patterns. For this reason, evaluating potential impacts using climate scenarios based on models exhibiting different regional responses is a necessary step to ensuring a representative analysis. Utilizing an even more encompassing set of scenarios in the future could help move from mainly qualitative toward more certain and quantitative conclusions.


2009 ◽  
Vol 22 (23) ◽  
pp. 6456-6476 ◽  
Author(s):  
Caio A. S. Coelho ◽  
Lisa Goddard

Abstract El Niño brings widespread drought (i.e., precipitation deficit) to the tropics. Stronger or more frequent El Niño events in the future and/or their intersection with local changes in the mean climate toward a future with reduced precipitation would exacerbate drought risk in highly vulnerable tropical areas. Projected changes in El Niño characteristics and associated teleconnections are investigated between the twentieth and twenty-first centuries. For climate change models that reproduce realistic oceanic variability of the El Niño–Southern Oscillation (ENSO) phenomenon, results suggest no robust changes in the strength or frequency of El Niño events. These models exhibit realistic patterns, magnitude, and spatial extent of El Niño–induced drought patterns in the twentieth century, and the teleconnections are not projected to change in the twenty-first century, although a possible slight reduction in the spatial extent of droughts is indicated over the tropics as a whole. All model groups investigated show similar changes in mean precipitation for the end of the twenty-first century, with increased precipitation projected between 10°S and 10°N, independent of the ability of the models to replicate ENSO variability. These results suggest separability between climate change and ENSO-like climate variability in the tropics. As El Niño–induced precipitation drought patterns are not projected to change, the observed twentieth-century variability is used in combination with model-projected changes in mean precipitation for assessing year-to-year drought risk in the twenty-first century. Results suggest more locally consistent changes in regional drought risk among models with good fidelity in reproducing ENSO variability.


Author(s):  
Hugh Tuffen

Glaciers and ice sheets on many active volcanoes are rapidly receding. There is compelling evidence that melting of ice during the last deglaciation triggered a dramatic acceleration in volcanic activity. Will melting of ice this century, which is associated with climate change, similarly affect volcanic activity and associated hazards? This paper provides a critical overview of the evidence that current melting of ice will increase the frequency or size of hazardous volcanic eruptions. Many aspects of the link between ice recession and accelerated volcanic activity remain poorly understood. Key questions include how rapidly volcanic systems react to melting of ice, whether volcanoes are sensitive to small changes in ice thickness and how recession of ice affects the generation, storage and eruption of magma at stratovolcanoes. A greater frequency of collapse events at glaciated stratovolcanoes can be expected in the near future, and there is strong potential for positive feedbacks between melting of ice and enhanced volcanism. Nonetheless, much further research is required to remove current uncertainties about the implications of climate change for volcanic hazards in the twenty-first century.


2006 ◽  
Vol 19 (11) ◽  
pp. 2597-2616 ◽  
Author(s):  
Gerald A. Meehl ◽  
Warren M. Washington ◽  
Benjamin D. Santer ◽  
William D. Collins ◽  
Julie M. Arblaster ◽  
...  

Abstract Climate change scenario simulations with the Community Climate System Model version 3 (CCSM3), a global coupled climate model, show that if concentrations of all greenhouse gases (GHGs) could have been stabilized at the year 2000, the climate system would already be committed to 0.4°C more warming by the end of the twenty-first century. Committed sea level rise by 2100 is about an order of magnitude more, percentage-wise, compared to sea level rise simulated in the twentieth century. This increase in the model is produced only by thermal expansion of seawater, and does not take into account melt from ice sheets and glaciers, which could at least double that number. Several tenths of a degree of additional warming occurs in the model for the next 200 yr in the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) B1 and A1B scenarios after stabilization in the year 2100, but with twice as much sea level rise after 100 yr, and doubling yet again in the next 100 yr to 2300. At the end of the twenty-first century, the warming in the tropical Pacific for the A2, A1B, and B1 scenarios resembles an El Niño–like response, likely due to cloud feedbacks in the model as shown in an earlier version. Greatest warming occurs at high northern latitudes and over continents. The monsoon regimes intensify somewhat in the future warmer climate, with decreases of sea level pressure at high latitudes and increases in the subtropics and parts of the midlatitudes. There is a weak summer midlatitude soil moisture drying in this model as documented in previous models. Sea ice distributions in both hemispheres are somewhat overextensive, but with about the right ice thickness at the end of the twentieth century. Future decreases in sea ice with global warming are proportional to the temperature response from the forcing scenarios, with the high forcing scenario, A2, producing an ice-free Arctic in summer by the year 2100.


2016 ◽  
Vol 6 (1) ◽  
pp. 4-11
Author(s):  
Keith Schneider

Underlying so much of the economic and ecological turmoil unfolding in California and the rest of the world now is a slow collision between the operating systems of the resource-wasting, vertically managed twentieth century and the much more volatile ecological and economic conditions of the twenty-first century. This essay argues that California is leading the way in defining a new code to deal responsibly-and profitably-with climate change and its effects.


2021 ◽  
Vol 14 (15) ◽  
Author(s):  
Niloofar Rasoolzadeh-Darzi ◽  
Hassan Ahmad ◽  
Abolfazl Moeini ◽  
Baharak Motamedvaziri

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Sven Kunisch ◽  
Markus Menz ◽  
David Collis

Abstract The corporate headquarters (CHQ) of the multi-business enterprise, which emerged as the dominant organizational form for the conduct of business in the twentieth century, has attracted considerable scholarly attention. As the business environment undergoes a fundamental transition in the twenty-first century, we believe that understanding the evolving role of the CHQ from an organization design perspective will offer unique insights into the nature of business activity in the future. The purpose of this article, in keeping with the theme of the Journal of Organization Design Special Collection, is thus to invigorate research into the CHQ. We begin by explicating four canonical questions related to the design of the CHQ. We then survey fundamental changes in the business environment occurring in the twenty-first century, and discuss their potential implications for CHQ design. When suitable here we also refer to the contributions published in our Special Collection. Finally, we put forward recommendations for advancements and new directions for future research to foster a deeper and broader understanding of the topic. We believe that we are on the cusp of a change in the CHQ as radical as that which saw its initial emergence in the late nineteenth/early twentieth century. Exactly what form that change will take remains for practitioners and researchers to inform.


Author(s):  
Hyun Min Sung ◽  
Jisun Kim ◽  
Sungbo Shim ◽  
Jeong-byn Seo ◽  
Sang-Hoon Kwon ◽  
...  

AbstractThe National Institute of Meteorological Sciences-Korea Meteorological Administration (NIMS-KMA) has participated in the Coupled Model Inter-comparison Project (CMIP) and provided long-term simulations using the coupled climate model. The NIMS-KMA produces new future projections using the ensemble mean of KMA Advanced Community Earth system model (K-ACE) and UK Earth System Model version1 (UKESM1) simulations to provide scientific information of future climate changes. In this study, we analyze four experiments those conducted following the new shared socioeconomic pathway (SSP) based scenarios to examine projected climate change in the twenty-first century. Present day (PD) simulations show high performance skill in both climate mean and variability, which provide a reliability of the climate models and reduces the uncertainty in response to future forcing. In future projections, global temperature increases from 1.92 °C to 5.20 °C relative to the PD level (1995–2014). Global mean precipitation increases from 5.1% to 10.1% and sea ice extent decreases from 19% to 62% in the Arctic and from 18% to 54% in the Antarctic. In addition, climate changes are accelerating toward the late twenty-first century. Our CMIP6 simulations are released to the public through the Earth System Grid Federation (ESGF) international data sharing portal and are used to support the establishment of the national adaptation plan for climate change in South Korea.


2013 ◽  
Vol 138 (1) ◽  
pp. 129-174 ◽  
Author(s):  
Matthew Pritchard

AbstractThis article examines a range of writings on the status of musical interpretation in Austria and Germany during the early decades of the twentieth century, and argues their relevance to current debates. While the division outlined by recent research between popular-critical hermeneutics and analytical ‘energetics’ at this time remains important, hitherto neglected contemporary reflections by Paul Bekker and Kurt Westphal demonstrate that the success of energetics was not due to any straightforward intellectual victory. Rather, the images of force and motion promoted by 1920s analysis were carried by historical currents in the philosophy, educational theory and arts of the time, revealing a culturally situated source for twenty-first-century analysis's preoccupations with motion and embodiment. The cultural relativization of such images may serve as a retrospective counteraction to the analytical rationalizing processes that culminated specifically in Heinrich Schenker's later work, and more generally in the privileging of graphic and notational imagery over poetic paraphrase.


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