Midterm nil

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Megatrends 2100 Mid-Term Presentation Nilufer D.


Cloud Albedo


Changes in climate depend essentially on 3 basic parameters, the amount of incident sunlight, the fraction of this sunlight that is reflected by the Earth, and the trapping of the Earth's infrared radiation by greenhouse gases.

The Earth's reflectance of the Sun's radiation back to space (ALBEDO) is the least well studied of the three.


The net cloud radiative forcing is about -13 watts per square meter


Clouds are very poorly parameterised in climate models.Thus, the scale of these variations presents a fundamental, and as yet unmet, challenge to understanding and predicting the Earth's climate.


Clouds both reflect sunlight, which cools the Earth, and trap heat in the same way as greenhouse gases, thus warming the Earth. Different types of clouds do more of one than the other.


The albedo of low thick clouds is about 90 percent. The albedo of high thin clouds may be as low as 10 percent.


Low, thick clouds primarily reflect solar radiation and cool the surface of the Earth. High, thin clouds primarily transmit incoming solar radiation; at the same time, they trap some of the outgoing infrared radiation emitted by the Earth and radiate it back downward, thereby warming the surface of the Earth.


A cloudless Earth would absorb nearly 20 percent more heat from the sun than the present Earth does


Clouds affect the climate but changes in the climate, in turn, affect the clouds. This relationship creates a complicated system of climate feedbacks, in which clouds modulate Earth's radiation and water balances.


The most up-to-date cloud data, released in August 2005 from the International Satellite Cloud Climatology Project (ISCCP),a careful compilation of cloud observations covering the entire Earth from a range of meteorological satellites, reveal that the explanation of this seeming anomaly lies primarily in a redistribution of the clouds.


Whereas low clouds have decreased during the most recent years, high clouds have increased to a larger extent, leading to both an increase in cloud amount (higher albedo) and an increased trapping of infrared radiation by clouds (increased heating).



How Cloud Albedo will change according to temperature variations of RCP’s scenarios?


How Cloud Albedo will change according to temperature variations of RCP’s scenarios?

Can Earth Temperature and Cloud Albedo increase together?


How Cloud Albedo will change according to temperature variations of RCP’s scenarios?

The RCP database aims at documenting the emissions, concentrations, and land-cover change projections of the so-called "Representative Concentration Pathways" (RCPs)

They are consistent sets of projections of only the components of radiative forcing that are meant to serve as input for climate modeling, pattern scaling, and atmospheric chemistry modeling.




How Cloud Albedo will change according to temperature variations of RCP’s scenarios?

Increase in temperature may allow more evaporation and hence more cloud formation. Biophysical effects (albedo, evapotranspiration surface roughness) may change, according to temperature changes.


Can Earth Temperature and Cloud Albedo increase together?

Increase in temperature may allow more evaporation and hence more cloud formation. Biophysical effects (albedo, evapotranspiration surface roughness) may change, according to temperature changes.


Target Audience To whom it may concern


Target Audience Students and Professors Data Scientist (mb junior one) Environmentalists Forecast scientist Sustainable manufacturing researchers People reasonably and very seriously concerned with climate change, want action to be taken to phase out fossil fuels


Target Audience Students and Professors Data Scientist (mb junior one) Environmentalists Forecast scientist Sustainable manufacturing researchers People reasonably and very seriously concerned with climate change, want action to be taken to phase out fossil fuels Nerdy scientific friends


Dataset


Satellite Cloud Climatology Project (ISCCP)








First sketches of visualisation


Alexander Calder








The 2005 update of the ISCCP data con firms an increasing global albedo since 2000, but this is only the most recent change in climatologically significant reflectance variations extending over the past two decades.


Thank you for attention


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