Effects of Nontropical Forest Cover on Climate

Otterman, J.; Chou, Ming-Dah; Arking, Albert

doi:10.1175/1520-0450(1984)023<0762:eonfco>2.0.co;2

Cited by 85 publications

(46 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Trees protrude the snow layer and hence decrease the high albedo of snow (Otterman et al, 1984). Additionally, vegetation reconstructions for the mid-Holocene show that boreal forest cover increased and expanded to the north.…”

Section: Introductionsupporting

confidence: 87%

“…In addition, δS est does not produce the reduction in net surface solar radiation of the region over North America between 40-60 • N and NorthEast Europe. We can support the statement that in our model the expansion of forest and its snow masking are the main land components that drive of the vegetation-climate interaction (Otterman et al, 1984;Harvey, 1988).…”

Section: Simulated Vegetation-climate Interactionmentioning

confidence: 99%

See 1 more Smart Citation

Strength of forest-albedo feedback in mid-Holocene climate simulations

2011

View full text Add to dashboard Cite

Abstract.Reconstructions of the mid-Holocene climate, 6000 years before present, suggest that spring temperatures were higher at high northern latitudes compared to the preindustrial period. A positive feedback between expansion of forest and climate presumably contributed to this warming. In the presence of snow, forests have a lower albedo than grass land. Therefore, the expansion of forest likely favoured a warming in spring, counteracting the lower insolation at the mid-Holocene.We investigate the sensitivity of the vegetation-atmosphere interaction under mid-Holocene orbital forcing with respect to the strength of the forest-albedo feedback by using a comprehensive coupled atmosphere-vegetation model (ECHAM5/JSBACH). We perform two sets of model simulations: a first set of simulations with a relatively weak reduction of albedo of snow by forest; and a second set of simulations with a relatively strong reduction of the albedo of snow by forest.We show that the parameterisation of the albedo of snow leads to uncertainties in the temperature signal. Compared to the set with weak snow masking, the simulations with strong snow masking reveal a spring warming that is three times higher, by 0.34 • C north of 60 • N. This warming is related to a forest expansion of only 13 %.

show abstract

Section: Introductionsupporting

confidence: 87%

Section: Simulated Vegetation-climate Interactionmentioning

confidence: 99%

Strength of forest-albedo feedback in mid-Holocene climate simulations

2011

View full text Add to dashboard Cite

show abstract

“…Otterman et al (1984) calculated the high-latitude atmosphere to be 4.6 • C cooler without the masking of snow from vegetation. Thomas and Rowntree (1992) demonstrated that boreal deforestation could increase land albedo and snow depth, and decrease surface temperature, net radiation, heat fluxes, and precipitation during spring.…”

Section: Background and Comparisons To Previous Workmentioning

confidence: 99%

High-latitude cooling associated with landscape changes from North American boreal forest fires

2013

View full text Add to dashboard Cite

Fires in the boreal forests of North America are generally stand-replacing, killing the majority of trees and initiating succession that may last over a century. Functional variation during succession can affect local surface energy budgets and, potentially, regional climate. Burn area across Alaska and Canada has increased in the last few decades and is projected to be substantially higher by the end of the 21st century because of a warmer climate with longer growing seasons. Here we simulated changes in forest composition due to altered burn area using a stochastic model of fire occurrence, historical fire data from national inventories, and succession trajectories derived from remote sensing. When coupled to an Earth system model, younger vegetation from increased burning cooled the high-latitude atmosphere, primarily in the winter and spring, with noticeable feedbacks from the ocean and sea ice. Results from multiple scenarios suggest that a doubling of burn area would cool the surface by 0.23 &pm; 0.09 °C across boreal North America during winter and spring months (December through May). This could provide a negative feedback to winter warming on the order of 3–5% for a doubling, and 14–23% for a quadrupling, of burn area. Maximum cooling occurs in the areas of greatest burning, and between February and April when albedo changes are largest and solar insolation is moderate. Further work is needed to integrate all the climate drivers from boreal forest fires, including aerosols and greenhouse gasses

show abstract

“…This seeming paradox has been called the "biome paradox" by Berger (2001) who supposes that mid-Holocene winter time warming might have been caused by strong vegetation-snow albedo feedback. According to Otterman et al (1984), more extended boreal forest, as reconstructed for mid-Holocene climate, could lead to a decrease in the surface albedo during the snowy season as snow-covered tall vegetation appears to be darker than snowcovered flat vegetation or bare ground. This, in turn, favours further warming due to reduced reflection of sunlight and further expansion of boreal forests (see also Foley et al, 1994;deNoblet et al, 1996;Texier et al, 1997;Foley, 2005).…”

Section: Demonstrated That In Theory Feedbacks Betweenmentioning

confidence: 99%

Late Quaternary vegetation-climate feedbacks

Claußen

2009

Clim. Past

View full text Add to dashboard Cite

Abstract. Feedbacks between vegetation and other components of the climate system are discussed with respect to their influence on climate dynamics during the late Quaternary, i.e., the last glacial-interglacial cycles. When weighting current understanding based on interpretation of palaeobotanic and palaeoclimatic evidence by numerical climate system models, a number of arguments speak in favour of vegetation dynamics being an amplifier of orbital forcing. (a) The vegetation-snow albedo feedback in synergy with the sea-ice albedo feedback tends to amplify Northern Hemisphere and global mean temperature changes. (b) Variations in the extent of the largest desert on Earth, the Sahara, appear to be amplified by biogeophysical feedback. (c) Biogeochemical feedbacks in the climate system in relation to vegetation migration are supposed to be negative on time scales of glacial cycles. However, with respect to changes in global mean temperature, they are presumably weaker than the positive biogeophysical feedbacks.

show abstract

Effects of Nontropical Forest Cover on Climate

Cited by 85 publications

References 0 publications

Strength of forest-albedo feedback in mid-Holocene climate simulations

Strength of forest-albedo feedback in mid-Holocene climate simulations

High-latitude cooling associated with landscape changes from North American boreal forest fires

Late Quaternary vegetation-climate feedbacks

Contact Info

Product

Resources

About