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| Titel |
Regional aerosol emissions and temperature response: Local and remote climate impacts of regional aerosol forcing |
| VerfasserIn |
Anna Lewinschal, Annica Ekman, Hans-Christen Hansson |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250151317
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| Publikation (Nr.) |
 EGU/EGU2017-15883.pdf |
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| Zusammenfassung |
| Emissions of anthropogenic aerosols vary substantially over the globe and the short
atmospheric residence time of aerosols leads to a highly uneven radiative forcing distribution,
both spatially and temporally. Regional aerosol radiative forcing can, nevertheless, exert a
large influence on the temperature field away from the forcing region through changes in heat
transport or the atmospheric or ocean circulation. Moreover, the global temperature response
distribution to aerosol forcing may vary depending on the geographical location of the
forcing. In other words, the climate sensitivity in one region can vary depending on the
location of the forcing.
The surface temperature distribution response to changes in sulphate aerosol
forcing caused by sulphur dioxide (SO2) emission perturbations in four different
regions is investigated using the Norwegian Earth System Model (NorESM). The
four regions, Europe, North America, East and South Asia, are all regions with
historically high aerosol emissions and are relevant from both an air-quality and
climate policy perspective. All emission perturbations are defined relative to the year
2000 emissions provided for the Coupled Model Intercomparison Project phase
5.
The global mean temperature change per unit SO2 emission change is similar for all four
regions for similar magnitudes of emissions changes. However, the global temperature
change per unit SO2 emission in simulations where regional SO2 emission were
removed is substantially higher than that obtained in simulations where regional SO2
emissions were increased. Thus, the climate sensitivity to regional SO2 emissions
perturbations depends on the magnitude of the emission perturbation in NorESM. On
regional scale, on the other hand, the emission perturbations in different geographical
locations lead to different regional temperature responses, both locally and in remote
regions.
The results from the model simulations are used to construct regional temperature
potential (RTP) coefficients, which directly link regional aerosol or aerosol precursor
emissions to the temperature response in different regions. These RTP coefficients can
provide a simplified way to perform an initial evaluation of climate impacts of e.g. different
emission policy pathways and pollution abatement strategies. |
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