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1.
Over the last 100?years, Arctic warming has resulted in a longer growing season in boreal and tundra ecosystems. This has contributed to a slow northward expansion of the boreal forest and a decrease in the surface albedo. Corresponding changes to the surface and atmospheric energy budgets have contributed to a broad region of warming over areas of boreal forest expansion. In addition, mesoscale and synoptic scale patterns have changed as a result of the excess energy at and near the surface. Previous studies have identified a relationship between the positioning of the boreal forest-tundra ecotone and the Arctic frontal zone in summer. This study examines the climate response to hypothetical boreal forest expansion and its influence on the summer Arctic frontal zone. Using the Weather Research and Forecasting model over the Northern Hemisphere, an experiment was performed to evaluate the atmospheric response to expansion of evergreen and deciduous boreal needleleaf forests into open shrubland along the northern boundary of the existing forest. Results show that the lower surface albedo with forest expansion leads to a local increase in net radiation and an average hemispheric warming of 0.6°C at and near the surface during June with some locations warming by 1–2°C. This warming contributes to changes in the meridional temperature gradient that enhances the Arctic frontal zone and strengthens the summertime jet. This experiment suggests that continued Northern Hemisphere high-latitude warming and boreal forest expansion might contribute to additional climate changes during the summer. 相似文献
2.
A temperate and boreal deforestation experiment has been performed at Météo-France using the ARPEGE climate model. A first
simulation was performed as a control with a present-day vegetation map, and another one with all forests north of 45 °N replaced
by meadows. Prescribed monthly mean climatological SSTs were used in both integrations. The ARPEGE climate model includes
a physically based land surface scheme, which has been tested both on snowfree and snow-covered sites, and has a relatively
high horizontal resolution. Results of the 4-year integrations suggest that forests exert a strong influence on the surface
climate of the temperate and boreal regions. Deforestation induces a significant cooling which modifies the atmospheric circulation
simulated in the high latitudes, and also in the tropics. The most important impact is observed during the melting season
which is delayed by the forest removal. This result is consistent with preliminary stand-alone experiments showing that the
atmospheric boundary layer can be heated by the forest, even if the ground is covered by snow. The study confirms that vegetation
feedbacks should be included when performing future climate studies such as doubled CO2 experiments, eventhough many uncertainties still remain with regard to other physical aspects of the climate models.
Received: 5 September 1995 / Accepted: 12 August 1996 相似文献
3.
Whendee L. Silver 《Climatic change》1998,39(2-3):337-361
Tropical forests are responsible for a large proportion of the global terrestrial C flux annually for natural ecosystems. Increased atmospheric CO2 and changes in climate are likely to affect the distribution of C pools in the tropics and the rate of cycling through vegetation and soils. In this paper, I review the literature on the pools and fluxes of carbon in tropical forests, and the relationship of these to nutrient cycling and climate. Tropical moist and humid forests have the highest rates of annual net primary productivity and the greatest carbon flux from soil respiration globally. Tropical dry forests have lower rates of carbon circulation, but may have greater soil organic carbon storage, especially at depths below 1 meter. Data from tropical elevation gradients were used to examine the sensitivity of biogeochemical cycling to incremental changes in temperature and rainfall. These data show significant positive correlations of litterfall N concentrations with temperature and decomposition rates. Increased atmospheric CO2 and changes in climate are expected to alter carbon and nutrient allocation patterns and storage in tropical forest. Modeling and experimental studies suggest that even a small increase in temperature and CO2 concentrations results in more rapid decomposition rates, and a large initial CO2 efflux from moist tropical soils. Soil P limitation or reductions in C:N and C:P ratios of litterfall could eventually limit the size of this flux. Increased frequency of fires in dry forest and hurricanes in moist and humid forests are expected to reduce the ecosystem carbon storage capacity over longer time periods. 相似文献
4.
5.
Over the last century, the Arctic has warmed at twice the rate of the planet as a whole. Observational evidence indicates that this rapid warming is affecting the tundra and boreal forest biomes by changing their structure and geographic distribution. A global climate model (GCM) was used to explore the atmospheric response to boreal forest expansion by applying a one-grid cell shift of the forest into tundra. This subtle shift is meant to represent the expansion that would occur this century rather than more extreme scenarios predicted by dynamic vegetation models. Results show that this shift causes an average annual warming of 0.3 °C over the region because of a reduction in the surface albedo and an increase in net radiation. A warming of ~1.0 °C occurs in spring when the forest masks the higher albedo snow-covered surface and results in snowmelt and a reduction in cloud cover. Results fail to show a larger-scale dynamical response although some warming of the lower and mid troposphere occurs in July. No changes were found in the position or strength of the Arctic frontal zone as some studies have indicated will occur with a shift in the boreal forest-tundra boundary. These findings suggest that coupled model simulations that predict larger changes in vegetation distribution are likely overemphasizing the amount of Arctic warming that will occur this century. These findings also indicate that a realistic dynamical response to subtle land cover change might not be correctly simulated by GCMs run at coarse spatial resolutions. 相似文献
6.
Sibyll Schaphoff Wolfgang Lucht Dieter Gerten Stephen Sitch Wolfgang Cramer I. Colin Prentice 《Climatic change》2006,74(1-3):97-122
This study investigates commonalities and differences in projected land biosphere carbon storage among climate change projections derived from one emission scenario by five different general circulation models (GCMs). Carbon storage is studied using a global biogeochemical process model of vegetation and soil that includes dynamic treatment of changes in vegetation composition, a recently enhanced version of the Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ-DGVM). Uncertainty in future terrestrial carbon storage due to differences in the climate projections is large. Changes by the end of the century range from −106 to +201 PgC, thus, even the sign of the response whether source or sink, is uncertain. Three out of five climate projections produce a land carbon source by the year 2100, one is approximately neutral and one a sink. A regional breakdown shows some robust qualitative features. Large areas of the boreal forest are shown as a future CO2 source, while a sink appears in the arctic. The sign of the response in tropical and sub-tropical ecosystems differs among models, due to the large variations in simulated precipitation patterns. The largest uncertainty is in the response of tropical rainforests of South America and Central Africa. 相似文献
7.
Abundant evidence indicates the growing season has been changed in the Alaskan terrestrial ecosystems in the last century as climate warms. Reasonable simulations of growing season length, onset, and ending are critical to a better understanding of carbon dynamics in these ecosystems. Recent ecosystem modeling studies have been slow to consider the interactive effects of soil thermal and hydrological dynamics on growing season changes in northern high latitudes. Here, we develop a coupled framework to model these dynamics and their effects on plant growing season at a daily time step. In this framework, we (1) incorporate a daily time step snow model into our existing hydrological and soil thermal models and (2) explicitly model the moisture effects on soil thermal conductivity and heat capacity and the effects of active layer depth and soil temperature on hydrological dynamics. The new framework is able to well simulate snow depth and soil temperature profiles for both boreal forest and tundra ecosystems at the site level. The framework is then applied to Alaskan boreal forest and tundra ecosystems for the period 1923–2099. Regional simulations show that (1) for the historical period, the growing season length, onset, and ending, estimated based on the mean soil temperature of the top 20 cm soils, and the annual cycle of snow dynamics, agree well with estimates based on satellite data and other approaches and (2) for the projected period, the plant growing season length shows an increasing trend in both tundra and boreal forest ecosystems. In response to the projected warming, by year 2099, (1) the snow-free days will be increased by 41.0 and 27.5 days, respectively, in boreal forest and tundra ecosystems and (2) the growing season lengths will be more than 28 and 13 days longer in boreal forest and tundra ecosystems, respectively, compared to 2010. Comparing two sets of simulations with and without considering feedbacks between soil thermal and hydrological dynamics, our analyses suggest coupling hydrological and soil thermal dynamics in Alaskan terrestrial ecosystems is important to model ecosystem dynamics, including growing season changes. 相似文献
8.
Sensitivity of terrestrial carbon storage to CO2-induced climate change: Comparison of four scenarios based on general circulation models 总被引：3，自引：0，他引：3
The potential impacts of CO2-induced climate change on terrestrial carbon storage was estimated using the Holdridge Life-Zone Classification and four climate change scenarios derived from general circulation models. Carbon values were assigned to life-zones and their associated soils from published studies. All four scenarios suggest an increase in area occupied by forests although details of predicted patterns vary among the scenarios. There is a poleward shift of the forested zones, with an increase in the areal extent of tropical forests and a shift of the boreal forest zone into the region currently occupied by tundra. Terrestrial carbon storage increased from 0.4% (8.5 Gt) to 9.5% (180.5 Gt) above estimates for present conditions. These changes represent a potential reduction of 4 to 85 ppm on elevated atmospheric CO2 levels. 相似文献
9.
Potential impact of albedo incorporation in boreal forest sector climate change policy effectiveness
Forests have an important role to play in climate change mitigation through carbon sequestration and wood supply. However, the lower albedo of mature forests compared to bare land implies that focusing only on GHG accounting may lead to biased estimates of forestry's total climatic impacts. An economic model with a high degree of detail of the Norwegian forestry and forest industries is used to simulate GHG fluxes and albedo impacts for the next decades. Albedo is incorporated in a carbon tax/subsidy scheme in the Norwegian forest sector using a partial, spatial equilibrium model. While a price of EU€100/tCO2e that targets GHG fluxes only results in reduced harvests, the same price including albedo leads to harvest levels that are five times higher in the first five years, with 39% of the national productive forest land base being cleared. The results suggest that policies that only consider GHG fluxes and ignore changes in albedo will not lead to an optimal use of the forest sector for climate change mitigation.Policy relevanceBare land reflects a larger share of incoming solar energy than dense forest and thus has higher albedo. Earlier research has suggested that changes in albedo caused by management of boreal forest may be as important as carbon fluxes for the forest's overall global warming impacts. The presented analysis is the first attempt to link albedo to national-scale forest climate policies. A policy with subsidies to forest owners that generate carbon sequestration and taxes levied on carbon emissions leads to a reduced forest harvest. However, including albedo in the policy alongside carbon fluxes yields very different results, causing initial harvest levels to increase substantially. The inclusion of albedo impacts will make harvests more beneficial for climate change mitigation as compared to a carbon-only policy. Hence, it is likely that carbon policies that ignore albedo will not lead to optimal forest management for climate change mitigation. 相似文献
10.
Arctic ecosystems could provide a substantial positive feedback to global climate change if warming stimulates below-ground CO2 release by enhancing decomposition of bulk soil organic matter reserves.Ecosystem respiration during winter is important in this context because CO2 release from snow-covered tundra soils is a substantial component of annual net carbon (C) balance, and because global climate models predict that the most rapid rises in regional air temperature will occur in the Arctic during winter. In this manipulative field study, the relative contributions of plant and bulk soil organic matter C pools to ecosystem CO2 production in mid-winter were investigated. We measured CO2 efflux rates in Swedish sub-arctic heath tundra from control plots and from plots that had been clipped in the previous growing season to disrupt plant activity. Respiration derived from recently-fixed plant C (i.e., plant respiration, and respiration associated with rhizosphere exudates and decomposition of fresh litter) was the principal source of CO2 efflux, while respiration associated with decomposition of bulk soil organic matter was low, and appeared relatively insensitive to temperature. These results suggest that warmer mid-winter temperatures in the Arctic may have a much greater impact on the cycling of recently-fixed, plant-associated C pools than on the depletion of tundra bulk soil C reserves, and consequently that there is a low potential for significant initial feedbacks from arctic ecosystems to climate change during mid-winter. 相似文献
11.
Guy Schurgers Uwe Mikolajewicz Matthias Gröger Ernst Maier-Reimer Miren Vizcaíno Arne Winguth 《Climate Dynamics》2007,29(4):357-373
Transient experiments for the Eemian (128–113 ky BP) were performed with a complex, coupled earth system model, including
atmosphere, ocean, terrestrial biosphere and marine biogeochemistry. In order to investigate the effect of land surface parameters
(background albedo, vegetation and tree fraction and roughness length) on the simulated changes during the Eemian, simulations
with interactive coupling between climate and vegetation were compared with additional experiments in which these feedbacks
were suppressed. The experiments show that the influence of land surface on climate is mainly caused by changes in the albedo.
For the northern hemisphere high latitudes, land surface albedo is changed partially due to the direct albedo effect of the
conversion of grasses into forest, but the indirect effect of forests on snow albedo appears to be the major factor influencing
the total absorption of solar radiation. The Western Sahara region experiences large changes in land surface albedo due to
the appearance of vegetation between 128 and 120 ky BP. These local land surface albedo changes can be as much as 20%, thereby
affecting the local as well as the global energy balance. On a global scale, latent heat loss over land increases more than
10% for 126 ky BP compared to present-day. 相似文献
12.
Annual CO2 Flux in Dry and Moist Arctic Tundra: Field Responses to Increases in Summer Temperatures and Winter Snow Depth 总被引：5，自引：0，他引：5
We examined the annual exchange of CO2 between the atmosphere and moist tussock and dry heath tundra ecosystems (which together account for over one-third of the low arctic land area) under ambient field conditions and under increased winter snow deposition, increased summer temperatures, or both. Our results indicate that these two arctic tundra ecosystems were net annual sources of CO2 to the atmosphere from September 1994 to September 1996 under ambient weather conditions and under our three climate change scenarios. Carbon was lost from these ecosystems in both winter and summer, although the majority of CO2 evolution took place during the short summer. Our results indicate that (1) warmer summer temperatures will increase annual CO2 efflux from both moist and dry tundra ecosystems by 45–55% compared to current ambient temperatures; (2) deeper winter snow cover will increase winter CO2 efflux in both moist and dry tundra ecosystems, but will decrease net summer CO2 efflux; and (3) deeper winter snow cover coupled with warmer summer temperatures will nearly double the annual amount of CO2 emitted from moist tundra and will result in a 24% increase in the annual CO2 efflux of dry tundra. If, as predicted, climate change alters both winter snow deposition and summer temperatures, then shifts in CO2 exchange between the biosphere and atmosphere will likely not be uniform across the Arctic tundra landscape. Increased snow deposition in dry tundra is likely to have a larger effect on annual CO2 flux than warmer summer temperatures alone or warmer temperatures coupled with increased winter snow depth. The combined effects of increased summer temperatures and winter snow deposition on annual CO2 flux in moist tundra will be much larger than the effects of either climate change scenario alone. 相似文献
13.
The participation of different vegetation types within the physical climate system is investigated using a coupled atmosphere-biosphere model, CCM3-IBIS. We analyze the effects that six different vegetation biomes (tropical, boreal, and temperate forests, savanna, grassland and steppe, and shrubland/tundra) have on the climate through their role in modulating the biophysical exchanges of energy, water, and momentum between the land-surface and the atmosphere. Using CCM3-IBIS we completely remove the vegetation cover of a particular biome and compare it to a control simulation where the biome is present, thereby isolating the climatic effects of each biome. Results from the tropical and boreal forest removal simulations are in agreement with previous studies while the other simulations provide new evidence as to their contribution in forcing the climate. Removal of the temperate forest vegetation exhibits behavior characteristic of both the tropical and boreal simulations with cooling during winter and spring due to an increase in the surface albedo and warming during the summer caused by a reduction in latent cooling. Removal of the savanna vegetation exhibits behavior much like the tropical forest simulation while removal of the grassland and steppe vegetation has the largest effect over the central United States with warming and drying of the atmosphere in summer. The largest climatic effect of shrubland and tundra vegetation removal occurs in DJF in Australia and central Siberia and is due to reduced latent cooling and enhanced cold air advection, respectively. Our results show that removal of the boreal forest yields the largest temperature signal globally when either including or excluding the areas of forest removal. Globally, precipitation is most affected by removal of the savanna vegetation when including the areas of vegetation removal, while removal of the tropical forest most influences the global precipitation excluding the areas of vegetation removal. 相似文献
14.
An 11-year remotely sensed surface albedo dataset coupled with historical meteorological and stand-level forest management data for a variety of stands in Norway’s most productive logging region is used to develop regression models describing temporal changes in forest albedo following clear-cut harvest disturbance events. Datasets are grouped by dominant tree species, and two alternate multiple regression models are developed and tested following a potential-modifier approach. This result in models with statistically significant parameters (p?<?0.05) that explain a large proportion of the observed variation, requiring a single canopy modifier predictor coupled with either monthly or annual mean air temperature as a predictor of a stand’s potential albedo. Models based on annual mean temperature predict annual albedo with errors (RMSE) in the range of 0.025–0.027, while models based on monthly mean temperature predict monthly albedo with errors ranging between of 0.057–0.065 depending on the dominant tree species. While both models have the potential to be transferable to other boreal regions with similar forest management regimes, further validation efforts are required. As active management of boreal forests is increasingly seen as a means to mitigate climate change, the presented models can be used with routine forest inventory and meteorological data to predict albedo evolution in managed forests throughout the region, which, together with carbon cycle modeling, can lead to more holistic climate impact assessments of alternative forest harvest scenarios and forest product systems. 相似文献
15.
Determining Effects of Area Burned and Fire Severity on Carbon Cycling and Emissions in Siberia 总被引：14，自引：0，他引：14
Susan G. Conard Anatoly I. Sukhinin Brian J. Stocks Donald R. Cahoon Eduard P. Davidenko Galina A. Ivanova 《Climatic change》2002,55(1-2):197-211
The Russian boreal forest contains about 25% of the global terrestrial biomass, and even a higher percentage of the carbon stored in litter and soils. Fire burns large areas annually, much of it in low-severity surface fires – but data on fire area and impacts or extent of varying fire severity are poor. Changes in land use, cover, and disturbance patterns such as those predicted by global climate change models, have the potential to greatly alter current fire regimes in boreal forests and to significantly impact global carbon budgets. The extent and global importance of fires in the boreal zone have often been greatly underestimated. For the 1998 fire season we estimate from remote sensing data that about 13.3 million ha burned in Siberia. This is about 5 times higher than estimates from the Russian Aerial Forest Protection Service (Avialesookhrana) for the same period. We estimate that fires in the Russian boreal forest in 1998 constituted some 14–20% of average annual global carbon emissions from forest fires. Average annual emissions from boreal zone forests may be equivalent to 23–39% of regional fossil fuel emissions in Canada and Russia, respectively. But the lack of accurate data and models introduces large potential errors into these estimates. Improved monitoring and understanding of the landscape extent and severity of fires and effects of fire on carbon storage, air chemistry, vegetation dynamics and structure, and forest health and productivity are essential to provide inputs into global and regional models of carbon cycling and atmospheric chemistry. 相似文献
16.
Terrestrial ecosystems provide a range of important services to humans, including global and regional climate regulation. These services arise from natural ecosystem functioning as governed by drivers such as climate, atmospheric carbon dioxide mixing ratio, and land-use change. From the perspective of carbon sequestration, numerous studies have assessed trends and projections of the past and future terrestrial carbon cycle, but links to the ecosystem service concept have been hindered by the lack of appropriate quantitative service metrics. The recently introduced concept of the Greenhouse Gas Value (GHGV) accounts for the land-atmosphere exchanges of multiple greenhouse gases by taking into consideration the associated ecosystem pool sizes, annual exchange fluxes and probable effects of natural disturbance in a time-sensitive manner.We use here GHGV as an indicator for the carbon sequestration aspects of the climate regulation ecosystem service, and quantify it at global scale using the LPJ-GUESS dynamic global vegetation model. The response of ecosystem dynamics and ecosystem state variables to trends in climate, atmospheric carbon dioxide levels and land use simulated by LPJ-GUESS are used to calculate the contribution of carbon dioxide to GHGV. We evaluate global variations in GHGV over historical periods and for future scenarios (1850–2100) on a biome basis following a high and a low emission scenario.GHGV is found to vary substantially depending on the biogeochemical processes represented in LPJ-GUESS (e.g. carbon–nitrogen coupling, representation of land use). The consideration of disturbance events that occur as part of an ecosystem's natural dynamics is crucial for realistic GHGV assessments; their omission results in unrealistically high GHGV. By considering the biome-specific response to current climate and land use, and their projections for the future, we highlight the importance of all forest biomes for maintaining and increasing biogeochemical carbon sequestration. Under future climate and carbon dioxide levels following a high emission scenario GHGV values are projected to increase, especially so in tropical forests, but land-use change (e.g. deforestation) opposes this trend. The GHGV of ecosystems, especially when assessed over large areas, is an appropriate metric to assess the contribution of different greenhouse gases to climate and forms a basis for the monetary valuation of the climate regulation service ecosystems provide. 相似文献
17.
18.
Jian Ni 《Climatic change》2002,55(1-2):61-75
The BIOME3 model was used to simulate the distribution patterns and carbon storage of the horizontal, zonal boreal forests in northeast and northwest China using a mapping system for vegetation patterns combined with carbon density estimates from vegetation and soils. The BIOME3 prediction is in reasonable good agreement with the potential distribution of Chinese boreal forests. The effects of changing atmospheric CO2 concentration had a nonlinear effect on boreal forest distribution, with 3.5–10.8% reduced areas for both increasing and decreasing CO2. In contrast, the increased climate together with and without changing CO2 concentration showed dramatic changes in geographic patterns, with 70% reduction in area and disappearance of almost boreal forests in northeast China. The baseline carbon storage in boreal forests of China is 4.60 PgC (median estimate) based on the vegetation area of actual boreal forest distribution. If taking the large area of agricultural crops into account, the median value of potential carbon storage is 6.92 PgC. The increasing (340–500 ppmv) and decreasing CO2 concentration (340–200 ppmv) led to decrease of carbon storage, 0.33 PgC and 1.01 PgC respectively compared to BIOME3 potential prediction under present climate and CO2 conditions. Both climate change alone and climate change with CO2 enrichment (340–500 ppmv) reduced largely the carbon stored in vegetation and soils by ca. 6.5 PgC. The effect of climate change is more significant than the direct physiological effect of CO2 concentration on the boreal forests of China, showing a large reduction in both distribution area and carbon storage. 相似文献
19.
Human activities have altered the distribution and quality of terrestrial ecosystems. Future demands for goods and services from terrestrial ecosystems will occur in a world experiencing human-induced climate change. In this study, we characterize the range in response of unmanaged ecosystems in the conterminous U.S. to 12 climate change scenarios. We obtained this response by simulating the climatically induced shifts in net primary productivity and geographical distribution of major biomes in the conterminous U.S. with the BIOME 3 model. BIOME 3 captured well the potential distribution of major biomes across the U.S. under baseline (current) climate. BIOME 3 also reproduced the general trends of observed net primary production (NPP) acceptably. The NPP projections were reasonable for forests, but not for grasslands where the simulated values were always greater than those observed. Changes in NPP would be most severe under the BMRC climate change scenario in which severe changes in regional temperatures are projected. Under the UIUC and UIUC + Sulfate scenarios, NPP generally increases, especially in the West where increases in precipitation are projected to be greatest. A CO2-fertilization effect either amplified increases or alleviated losses in modeled NPP. Changes in NPP were also associated with changes in the geographic distribution of major biomes. Temperate/boreal mixed forests would cover less land in the U.S. under most of the climate change scenarios examined. Conversely, the temperate conifer and temperate deciduous forests would increase in areal extent under the UIUC and UIUC + Sulfate scenarios. The Arid Shrubland/Steppe would spread significantly across the southwest U.S. under the BMRC scenario. A map overlay of the simulated regions that would lose or gain capacity to produce corn and wheat on top of the projected distribution of natural ecosystems under the BMRC and UIUC scenarios (Global mean temperature increase of +2.5 °C, no CO2 effect) helped identify areas where natural and managed ecosystems could contract or expand. The methods and models employed here are useful in identifying; (a) the range in response of unmanaged ecosystem in the U.S. to climate change and (b) the areas of the country where, for a particular scenario of climate change, land cover changes would be most likely. 相似文献
20.
Much research focuses on how the terrestrial biosphere influences climate through changes in surface albedo (reflectivity), stomatal conductance and leaf area index (LAI). By using a fully-coupled GCM (HadCM3LC), our research objective was to induce an increase in the growth of global vegetation to isolate the effect of increased LAI on atmospheric exchange of heat and moisture. Our Control simulation had a mean global net primary production (NPP) of 56.3 GtCyr?1 which is half that of our scenario value of 115.1 GtCyr?1. LAI and latent energy (Q E) were simulated to increase globally, except in areas around Antarctica. A highly productive biosphere promotes mid-latitude mean surface cooling of ~2.5°C in the summer, and surface warming of ~1.0°C in the winter. The former response is primarily the result of reduced Bowen ratio (i.e. increased production of Q E) in combination with small increases in planetary albedo. Response in winter temperature is likely due to decreased planetary albedo that in turn permits a greater amount of solar radiation to reach the Earth’s surface. Energy balance calculations show that between 75° and 90°N latitude, an additional 2.4 Wm?2 of surface heat must be advected into the region to maintain energy balance, and ultimately causes high northern latitudes to warm by up to 3°C. We postulate that large increases in Q E promoted by increased growth of terrestrial vegetation could contribute to greater surface-to-atmosphere exchange and convection. Our high growth simulation shows that convective rainfall substantially increases across three latitudinal bands relative to Control; in the tropics, across the monsoonal belt, and in mid-latitude temperate regions. Our theoretical research has implications for applied climatology; in the modeling of past “hot-house” climates, in explaining the greening of northern latitudes in modern-day times, and for predicting future changes in surface temperature with continued increases in atmospheric CO2. 相似文献