Abstract The Miocene epoch (23.03ā5.33 Ma) was a time interval of global warmth, relative to today. Continental configurations and mountain topography transitioned toward modern conditions, and many flora and fauna evolved into the same taxa that exist today. Miocene climate was dynamic: long periods of early and late glaciation bracketed a ā¼2 Myr greenhouse intervalāthe Miocene Climatic Optimum (MCO). Floras, faunas, ice sheets, precipitation,pCO2, and ocean and atmospheric circulation mostly (but not ubiquitously) covaried with these large changes in climate. With higher temperatures and moderately higherpCO2(ā¼400ā600 ppm), the MCO has been suggested as a particularly appropriate analog for future climate scenarios, and for assessing the predictive accuracy of numerical climate modelsāthe same models that are used to simulate future climate. Yet, Miocene conditions have proved difficult to reconcile with models. This implies either missing positive feedbacks in the models, a lack of knowledge of past climate forcings, or the need for reāinterpretation of proxies, which might mitigate the modelādata discrepancy. Our understanding of Miocene climatic, biogeochemical, and oceanic changes on broad spatial and temporal scales is still developing. New records documenting the physical, chemical, and biotic aspects of the Earth system are emerging, and together provide a more comprehensive understanding of this important time interval. Here, we review the stateāofātheāart in Miocene climate, ocean circulation, biogeochemical cycling, ice sheet dynamics, and biotic adaptation research as inferred through proxy observations and modeling studies.
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An estimate for š¹-jumping numbers via the roots of the Bernstein-Sato polynomial
- Award ID(s):
- 2001132
- PAR ID:
- 10527385
- Publisher / Repository:
- American Mathematical Society
- Date Published:
- Journal Name:
- Proceedings of the American Mathematical Society
- ISSN:
- 0002-9939
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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