Repository logo
 

The role of historical land-cover changes as a mechanism for global and regional climate change

dc.contributor.authorChase, Thomas N. (Thomas Newell), 1962-, author
dc.date.accessioned2007-01-03T07:44:54Z
dc.date.available2007-01-03T07:44:54Z
dc.date.issued1999
dc.description.abstractThis paper describes the results from several modeling studies and an observational analysis as to the effect of historical land-cover change on regional and global climates. We discuss methods for determining historical vegetation change and present results from model simulations at the global and regional scale which compare climates generated using currently observed vegetation versus natural vegetation as a boundary condition. We also compare these modeling studies with recent observational data and with simulations of climate change resulting from increased greenhouse gases. We conclude from this research that vegetation change, as it has already occurred, globally and regionally, can have significant effects on both global and regional climates. These effects are not limited to the regions of direct land-cover change forcing. For example, as a result of tropical deforestation, the position and intensity of the ITCZ is affected by the change in land surface characteristics resulting in global-scale effects which are similar in nature to the climatic effects associated with El NiƱo Southern Oscillation (ENSO). These include changes in high-latitude circulations, the generation of low frequency waves which appear to propagate to the extratropics in well-defined teleconnection patterns, and reduced low-level easterlies over most of the topical Pacific basin under current vegetation. This implies an interaction mechanism between tropical deforestation and ENSO. The model simulations of climate change due to land-cover change compare favorably in spatial patterns and amplitude with recently observed temperature trends. Additionally, a comparison between simulations of climate changes due to land-cover disturbance and changes due to rising atmospheric CO2 concentration show that global land-cover changes as they have already occurred, are responsible for shifts in climate which are of similar amplitude and occur in the same regions as simulated climate changes resulting from increased CO2. A comparison of three independent observational datasets shows strong disagreement not only in the sign of recent globally-averaged temperature trends but also disagree as to regions where significant climate shifts are occurring. Unlike model simulations of greenhouse gas warming, warm anomalies do not occur preferentially over land during this period and do not increase with height in the tropics.
dc.format.mediumdoctoral dissertations
dc.identifier1999_Spring_Chase_Thomas.pdf
dc.identifierETDF1999100003ECOL
dc.identifier.urihttp://hdl.handle.net/10217/60539
dc.languageEnglish
dc.language.isoeng
dc.publisherColorado State University. Libraries
dc.relationCatalog record number (MMS ID): 991007042929703361
dc.relationQC852.C6 no.685
dc.relation.ispartof1980-1999
dc.rightsCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.
dc.subject.lcshClimatic changes
dc.subject.lcshVegetation and climate
dc.titleThe role of historical land-cover changes as a mechanism for global and regional climate change
dc.typeText
dcterms.rights.dplaThis Item is protected by copyright and/or related rights (https://rightsstatements.org/vocab/InC/1.0/). You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
thesis.degree.disciplineEcology
thesis.degree.grantorColorado State University
thesis.degree.levelDoctoral
thesis.degree.nameDoctor of Philosophy (Ph.D.)

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
1999_Spring_Chase_Thomas_2.pdf
Size:
10.02 MB
Format:
Adobe Portable Document Format
Description: