AMAD
„Archivum Medii Aevi Digitale - Interdisziplinäres Open-Access-Fachrepositorium und Wissenschaftsblog für Mittelalterforschung‟Zur Einreichung
| Datum: | 2007 |
| Titel: | Tropical Pacific Forcing of North American Medieval Megadroughts: Testing the Concept with an Atmosphere Model Forced by Coral-Reconstructed SSTs* |
| Mitwirkende: | The Pennsylvania State University CiteSeerX Archives |
| Autor*in: | Jennifer Miller Richard Seager Robert Burgman Amy Clement Naomi Naik |
| Beschreibung: | The possible role that tropical Pacific SSTs played in driving the megadroughts over North America during the medieval period is addressed. Fossil coral records from the Palmyra Atoll are used to derive tropical Pacific SSTs for the period from A.D. 1320 to A.D. 1462 and show overall colder conditions as well as extended multidecadal La Niña–like states. The reconstructed SSTs are used to force a 16-member ensemble of atmosphere GCM simulations, each with different initial conditions, with the atmosphere coupled to a mixed layer ocean outside of the tropical Pacific. Model results are verified against North American tree ring reconstructions of the Palmer Drought Severity Index. A singular value decomposition analysis is performed using the soil moisture anomaly simulated by another 16-member ensemble of simulations forced by global observed SSTs for 1856–2004 and tree ring reconstructions of the Palmer Drought Severity Index for the same period. This relationship is used to transfer the modeled medieval soil moisture anomaly (relative to the modern simulation) into a model-estimated Palmer Drought Severity Index. The model-estimated Palmer Drought Severity Index reproduces many aspects of both the interannual and decadal variations of the tree ring reconstructions, in addition to an overall drier climate that is drier than the tree ring records suggest. The model-estimated Palmer Drought Severity Index simulates two previously |
| URI: | https://www.amad.org/jspui/handle/123456789/77365 |
| Quelle: | http://www.ldeo.columbia.edu/res/div/ocp/pub/seager/Seager_etal_megadroughts.pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.177.6395 |
| AMAD ID: | 568088 |
| Enthalten in den Sammlungen: | BASE (Bielefeld Academic Search Engine) General history of Europe |
