2) Rainfall is influenced by
feedback from vegetation.
In all of these simple models, we assume the atmosphere to have a volume as fixed as a bathtub, we assume that the atmosphere / ocean system is a closed system, we assume that the incoming radiation from the Sun is constant, we assume no turbulence, we assume no viscosity, we assume radiative equilibrium with no feedback lag, we take no account of water vapor flux assuming it to be constant, no change in albedo from changes in land use, glacier lengthening and shortening, no volcanic eruptions,
no feedbacks from vegetation.
Not exact matches
Factoring in slow
feedbacks from ice and
vegetation changes would generate a significantly higher ECS, likely in the 4 to 6 C (7.2 to 10.8 F) range, the paper notes.
Using information
from pre-historic climate archives, Zeebe calculated how slow climate
feedbacks (land ice,
vegetation, etc.) and climate sensitivity may evolve over time.
General circulation models have generally excluded the
feedback between climate and the biosphere, using static
vegetation distributions and CO2 concentrations
from simple carbon - cycle models that do not include climate change6.
-- 7) Forest models for Montana that account for changes in both climate and resulting
vegetation distribution and patterns; 8) Models that account for interactions and
feedbacks in climate - related impacts to forests (e.g., changes in mortality
from both direct increases in warming and increased fire risk as a result of warming); 9) Systems thinking and modeling regarding climate effects on understory
vegetation and interactions with forest trees; 10) Discussion of climate effects on urban forests and impacts to cityscapes and livability; 11) Monitoring and time - series data to inform adaptive management efforts (i.e., to determine outcome of a management action and, based on that outcome, chart future course of action); 12) Detailed decision support systems to provide guidance for managing for adaptation.
A 2008 study led by James Hansen found that climate sensitivity to «fast
feedback processes» is 3 °C, but when accounting for longer - term
feedbacks (such as ice sheet disintegration,
vegetation migration, and greenhouse gas release
from soils, tundra or ocean), if atmospheric CO2 remains at the doubled level, the sensitivity increases to 6 °C based on paleoclimatic (historical climate) data.
General circulation models have generally excluded the
feedback between climate and the biosphere, using static
vegetation distributions and CO2 concentrations
from simple carbon - cycle models that do not include climate change6.
Earth system and carbon - cycle
feedbacks such as the release of carbon
from thawing permafrost or
vegetation changes affecting terrestrial carbon storage or albedo may further extend and possibly amplify warming (6).
Based on evidence
from Earth's history, we suggest here that the relevant form of climate sensitivity in the Anthropocene (e.g.
from which to base future greenhouse gas (GHG) stabilization targets) is the Earth system sensitivity including fast
feedbacks from changes in water vapour, natural aerosols, clouds and sea ice, slower surface albedo
feedbacks from changes in continental ice sheets and
vegetation, and climate — GHG
feedbacks from changes in natural (land and ocean) carbon sinks.
Ecosystem
Feedbacks from Carbon and Water Cycle Changes —
Vegetation changes in the Amazon Basin 5.
Indeed, the long lifetime of fossil fuel carbon in the climate system and persistence of the ocean warming ensure that «slow»
feedbacks, such as ice sheet disintegration, changes of the global
vegetation distribution, melting of permafrost, and possible release of methane
from methane hydrates on continental shelves, would also have time to come into play.
States that other
feedbacks likely to emerge are those in which key processes include surface fluxes of trace gases, changes in the distribution of
vegetation, changes in surface soil moisture, changes in atmospheric water vapor arising
from higher temperatures and greater areas of open ocean, impacts of Arctic freshwater fluxes on the meridional overturning circulation of the ocean, and changes in Arctic clouds resulting
from changes in water vapor content
The remaining slow drift to lower GMT and pCO2 over glacial time, punctuated by higher - frequency variability and the dust − climate
feedbacks, may reflect the consequences of the growth of continental ice sheets via albedo increases (also
from vegetation changes) and increased CO2 dissolution in the ocean
from cooling.
We calculate land ice, sea ice and
vegetation feedbacks for the 18K climate to be fland ice ∼ 1.2 - 1.3, fsea ice ∼ 1.2, and fvegetation ∼ 1.01 - 1.1
from their effect on the radiation budget at the top of the atmosphere.
Stabilization of ca at the lower limit of 200 — 250 ppm during the past 24 Myr appears to result
from a strong negative
feedback in the form of attenuation of silicate rock weathering as terrestrial
vegetation approaches CO2 starvation [Pagani et al., 2009].
Burning
vegetation is a negative
feedback from aerosols.
They are yet to take into account the long - term
feedbacks from the melting of ice sheets and
vegetation changes.