Showing papers on "Runaway climate change published in 1992"

Time-dependent greenhouse warming computations with a coupled ocean-atmosphere model

Abstract: Climate changes during the next 100 years caused by anthropogenic emissions of greenhouse gases have been simulated for the Intergovernmental Panel on Climate Change Scenarios A (“business as usual”) and D (“accelerated policies”) using a coupled ocean-atmosphere general circulation model. In the global average, the near-surface temperature rises by 2.6 K in Scenario A and by 0.6 K in Scenario D. The global patterns of climate change for both IPCC scenarios and for a third step-function 2 x CO2 experiment were found to be very similar. The warming delay over the oceans is larger than found in simulations with atmospheric general circulation models coupled to mixed-layer models, leading to a more pronounced land-sea contrast and a weaker warming (and in some regions even an initial cooling) in the Southern Ocean. During the first forty years, the global warming and sea level rise due to the thermal expansion of the ocean are significantly slower than estimated previously from box-diffusion-upwelling models, but the major part of this delay can be attributed to the previous warming history prior to the start of present coupled ocean-atmosphere model integration (cold start).

Climate variability and the Atlantic Ocean

Abstract: Climate models indicate global warming ranging from 1.5°C to 4°C in response to a doubling in greenhouse gases. Whether this warming occurs in 50 years or 100 years is not certain, due in part to our limited understanding of natural climate variability. Apart from its intrinsic merit, the study of natural climate variability is motivated by the societal need to address climate change issues. From this perspective, the interannual to interdecadal time scales are of particular importance. These are precisely the time scales at which coupling to the ocean circulation becomes of paramount significance.

Global Warming: Physics and Facts

Abstract: This report contains papers on: A tutorial on global atmospheric energetics and the greenhouse effect; global climate models: what and how; comparison of general circulation models; climate and the earth`s radiation budget; temperature and sea level change; short-term climate variability and predictions; the great ocean conveyor; trace gases in the atmosphere: temporal and spatial trends; the geochemical carbon cycle and the uptake of fossil fuel CO{sub 2}; forestry and global warming; the physical and policy linkages; policy implications of greenhouse warming; options for lowering US carbon dioxide emissions; options for reducing carbon dioxide emissions; and science and diplomacy: a new partnership to protect the environment.

Abrupt warming of global climate in the 1980s

Abstract: , which enhances the greenhouse effect, is responsible for the warming of global climate in the 20th century, especially in the 1980s.

The role of clouds and oceans in global greenhouse warming

Abstract: During the past three years we have conducted several studies using models and a combination of satellite data, in situ meteorological and oceanic data, and paleoclimate reconstructions, under the DoE program, Quantifying the Link Between Change in Radiative Balance and Atmospheric Temperature''. Our goals were to investigate effects of global cloudiness variations on global climate and their implications for cloud feedback and continue development and application of NYU transient climate/ocean models, with emphasis on coupled effects of greenhouse warming and feedbacks by both the clouds and oceans. Our original research plan emphasized the use of cloud, surface temperature and ocean data sets interpreted by focused climate/ocean models to develop a cloud radiative forcing scenario for the past 100 years and to assess the transient climate response; to narrow key uncertainties in the system; and to identify those aspects of the climate system most likely to be affected by greenhouse warming over short, medium and long time scales.

The Study of Climate Change Using a Simplified Model with Combined Atmospheric-Hydrologic Processes

Abstract: This paper addresses the characteristics of climate change due to global warming using simplified climate model. The proposed model can take into account physics-based climate processes as well as the interactions between atmospheric and hydrologic processes in the mid-latitude. Since the present study simulates only the longitudinal climate change, the computational burden can be significantly reduced. The vertically and longitudinally averaged mean temperature and mean water vapor content between 30°N and 50°N latitudes are considered as atmospheric state variables, while soil and sea temperatures and water storage amount are considered for describing the behavior of hydrologic systems. Special attention is directed to the investigation of the various effects on the global warming using this model. The climate changes due to increasing CO2 are investigated in some numerical experiments.