Institut für Meteorologie und Klimaforschung

Seminar über Aerosolphysik (IMK-AAF)

Ansprechpartner: Prof. Dr. T. Leisner, Dr. H. Saathoff, Dr. R. Wagner

Das Seminar findet - soweit nicht extra angekündigt - Montags um 11:00 Uhr im Seminarraum 150 des IMK-Gebäudes 326 (Campus Nord) statt.

Veranstaltungskalender

 
Kolloquium

How might Climate Engineering Influence the Hydrological Cycle?

Dienstag, 20. Mai 2014, 16:30-17:30
KIT, Campus Süd, Institut für Meteorologie und Klimaforschung
IMK-TRO,Wolfgang-Gaede-Str.1, Geb.30.23,Physikhochhaus 13. Stock
Seminarraum
Abstract The so-called ‘2-degree target’ has been set as a tentative limit for global warming before serious disruptions in ecosystems and society may be expected. Despite political ambitions by e.g., the EU, global anthropogenic emissions of greenhouse gases continue to rise, casting doubt on the realism of the 2-degree target. Consequently, research on climate engineering, while still controversial, is receiving growing attention among climate scientists (IPCC AR5). Climate engineering covers two separate research areas: Greenhouse Gas Removal (GGR) and Radiation Management (RM). RM here refers to deliberate modifications of either incoming solar radiation or outgoing terrestrial radiation. Progress is being made in our understanding of the potential and side effects of RM through e.g. the Geoengineering Model Intercomparison Project (GeoMIP). Nevertheless, it must be stressed that the parameterizations on which these simulations rely are highly uncertain. Also, the feasibility and costs of any climate engineering techniques are still unknown. A robust result from multi-model experiments with Earth System Models is that if the incoming solar radiation is uniformly reduced, global warming can be suppressed, but only at the expense of a significant reduction in precipitation (Tilmes et al., 2013). Is that result a general feature of RM or just a consequence of the simple experimental design that was used? Specific ideas for carrying out RM include stratospheric sulfur injections (mimicking major volcanic eruptions), marine sky brightening, cirrus cloud thinning, desert brightening, crop brightening and urban brightening. While the last two are considered rather ineffective, both stratospheric sulfur injections and ‘cloud seeding’ may have a potential for significantly cooling the climate. But, what about possible side effects of these proposed methods, concerning e.g. the hydrological cycle? We will present results from recent and ongoing research on Radiation Management using Earth System Models, in which we address the above questions. For instance, Niemeier et al. (2013) obtained distincly different responses in the hydrological cycle for the three different radiation management techniques investigated (solar constant reduction, stratospheric sulfur injection, marine sky brightening). In their multi-model study, Alterskjær et al. (2013) found that marine sky brightening may modify the atmospheric circulation in such a way as to enhance moisture availability over low-latitude land areas. Cirrus cloud thinning seeks to counteract global warming by enhancing outgoing thermal radiation (Storelvmo et al., 2013), which is the part of the electromagnetic spectrum already being perturbed by anthropogenic greenhouse gases. According to Muri et al. (2014), this may have beneficial effects for the hydrological cycle compared to techniques that target solar radiation.
Diese Veranstaltung ist Teil der Reihe Karlsruher Meteorologisches Kolloquium
Referent/in
Prof. Dr. Jon Egill Kristjansson

University of Oslo
Veranstalter
Institut für Meteorologie und Klimaforschung
Karlsruher Institut für Technologie
Kaiserstraße 12
76131 Karlsruhe
E-Mail: sekr does-not-exist.imk-tro kit edu
https://www.imk-tro.kit.edu/
Servicemenü

Hinweise

"CS" - KIT-Campus Süd (Universität), Gebäude 30.23 (Physikhochhaus), Seminarraum 13/2

"CN" - KIT-Campus Nord (Forschungszentrum), Gebäude 435 (IMK), Raum 2.05

(Besucher bitte Personalausweis mitbringen!)