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Title: Modeling climate related feedback processes

Abstract

In order to assess their impact, the feedbacks which at present can be quantified reasonably are built into the Integrated Model to Assess the Greenhouse Effect (IMAGE). Unlike previous studies, this study describes the scenario- and time-dependent role of biogeochemical feedbacks. A number of simulation experiments are performed with IMAGE to project climate changes. Besides estimates of their absolute importance, the relative importance of individual biogeochemical feedbacks is considered by calculating the gain for each feedback process. This study focuses on feedback processes in the carbon cycle and the methane (semi-) cycle. Modeled feedbacks are then used to balance the past and present carbon budget. This results in substantially lower projections for atmospheric carbon dioxide than the Intergovernmental Panel on Climate Change (IPCC) estimates. The difference is approximately 18% from the 1990 level for the IPCC [open quotes]Business-as-Usual[close quotes] scenario. Furthermore, the IPCC's [open quotes]best guess[close quotes] value of the CO[sub 2] concentration in the year 2100 falls outside the uncertainty range estimated with our balanced modeling approach. For the IPCC [open quotes]Business-as-Usual[close quotes] scenario, the calculated total gain of the feedbacks within the carbon cycle appears to be negative, a result of the dominant role of the fertilization feedback.more » This study also shows that if temperature feedbacks on methane emissions from wetlands, rice paddies, and hydrates do materialize, methane concentrations might be increased by 30% by 2100. 70 refs., 17 figs., 7 tabs.« less

Authors:
;  [1]
  1. (National Inst. of Public Health and Environmental Protection, Bilthoven (Netherlands))
Publication Date:
OSTI Identifier:
5674440
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Environmental Science and Health, Part A: Environmental Science and Engineering; (United States); Journal Volume: 28:9
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 58 GEOSCIENCES; GREENHOUSE EFFECT; MATHEMATICAL MODELS; ALBEDO; BIOGEOCHEMISTRY; CARBON CYCLE; CARBON DIOXIDE; CLIMATE MODELS; FEEDBACK; METHANE; THEORETICAL DATA; ALKANES; CARBON COMPOUNDS; CARBON OXIDES; CHALCOGENIDES; CHEMISTRY; CLIMATIC CHANGE; DATA; GEOCHEMISTRY; HYDROCARBONS; INFORMATION; NUMERICAL DATA; ORGANIC COMPOUNDS; OXIDES; OXYGEN COMPOUNDS; 540110*; 580000 - Geosciences

Citation Formats

Elzen, M.G.J. den, and Rotmans, J.. Modeling climate related feedback processes. United States: N. p., 1993. Web. doi:10.1080/10934529309375997.
Elzen, M.G.J. den, & Rotmans, J.. Modeling climate related feedback processes. United States. doi:10.1080/10934529309375997.
Elzen, M.G.J. den, and Rotmans, J.. 1993. "Modeling climate related feedback processes". United States. doi:10.1080/10934529309375997.
@article{osti_5674440,
title = {Modeling climate related feedback processes},
author = {Elzen, M.G.J. den and Rotmans, J.},
abstractNote = {In order to assess their impact, the feedbacks which at present can be quantified reasonably are built into the Integrated Model to Assess the Greenhouse Effect (IMAGE). Unlike previous studies, this study describes the scenario- and time-dependent role of biogeochemical feedbacks. A number of simulation experiments are performed with IMAGE to project climate changes. Besides estimates of their absolute importance, the relative importance of individual biogeochemical feedbacks is considered by calculating the gain for each feedback process. This study focuses on feedback processes in the carbon cycle and the methane (semi-) cycle. Modeled feedbacks are then used to balance the past and present carbon budget. This results in substantially lower projections for atmospheric carbon dioxide than the Intergovernmental Panel on Climate Change (IPCC) estimates. The difference is approximately 18% from the 1990 level for the IPCC [open quotes]Business-as-Usual[close quotes] scenario. Furthermore, the IPCC's [open quotes]best guess[close quotes] value of the CO[sub 2] concentration in the year 2100 falls outside the uncertainty range estimated with our balanced modeling approach. For the IPCC [open quotes]Business-as-Usual[close quotes] scenario, the calculated total gain of the feedbacks within the carbon cycle appears to be negative, a result of the dominant role of the fertilization feedback. This study also shows that if temperature feedbacks on methane emissions from wetlands, rice paddies, and hydrates do materialize, methane concentrations might be increased by 30% by 2100. 70 refs., 17 figs., 7 tabs.},
doi = {10.1080/10934529309375997},
journal = {Journal of Environmental Science and Health, Part A: Environmental Science and Engineering; (United States)},
number = ,
volume = 28:9,
place = {United States},
year = 1993,
month =
}
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