دورية أكاديمية

A role for orbital eccentricity in Earth’s seasonal climate

التفاصيل البيبلوغرافية
العنوان: A role for orbital eccentricity in Earth’s seasonal climate
المؤلفون: John C. H. Chiang, Anthony J. Broccoli
المصدر: Geoscience Letters, Vol 10, Iss 1, Pp 1-14 (2023)
بيانات النشر: SpringerOpen, 2023.
سنة النشر: 2023
المجموعة: LCC:Science
LCC:Geology
مصطلحات موضوعية: Seasons, Orbital eccentricity, Tropical ocean–atmosphere interactions, Science, Geology, QE1-996.5
الوصف: Abstract The seasonality of Earth’s climate is driven by two factors: the tilt of the Earth’s rotation axis relative to the plane of its orbit (hereafter the tilt effect), and the variation in the Earth–Sun distance due to the Earth’s elliptical orbit around the Sun (hereafter the distance effect). The seasonal insolation change between aphelion and perihelion is only ~ 7% of the annual mean and it is thus assumed that the distance effect is not relevant for the seasons. A recent modeling study by the authors and collaborators demonstrated however that the distance effect is not small for the Pacific cold tongue: it drives an annual cycle there that is dynamically distinct and ~ 1/3 of the amplitude from the known annual cycle arising from the tilt effect. The simulations also suggest that the influence of distance effect is significant and pervasive across several other regional climates, in both the tropics and extratropics. Preliminary work suggests that the distance effect works its influence through the thermal contrast between the mostly ocean hemisphere centered on the Pacific Ocean (the ‘Marine hemisphere’) and the hemisphere opposite to it centered over Africa (the ‘Continental hemisphere’), analogous to how the tilt effect drives a contrast between the northern and southern hemispheres. We argue that the distance effect should be fully considered as an annual cycle forcing in its own right in studies of Earth’s modern seasonal cycle. Separately considering the tilt and distance effects on the Earth’s seasonal cycle provides new insights into the workings of our climate system, and of direct relevance to paleoclimate where there are outstanding questions for long-term climate changes that are related to eccentricity variations.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 2196-4092
Relation: https://doaj.org/toc/2196-4092
DOI: 10.1186/s40562-023-00313-7
URL الوصول: https://doaj.org/article/114dd40de2e2488fa38e136edf1e0c1e
رقم الأكسشن: edsdoj.114dd40de2e2488fa38e136edf1e0c1e
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:21964092
DOI:10.1186/s40562-023-00313-7