کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6442752 1639939 2016 89 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Indian winter monsoon: Present and past
ترجمه فارسی عنوان
موزون زمستان هند: حال و گذشته
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
چکیده انگلیسی
The Indian subcontinent receives most of its annual precipitation due to Indian summer (June, July, August and September) monsoon. Southeastern coastal region of the India receives significant amount of precipitation due to the northeast monsoon (October and November). Over northern Indian region almost one-third of annual precipitation is received during winter (December, January and February) by eastward moving extratropical cyclone called 'western disturbances (WDs)' in Indian meteorological parlance. Various studies are conducted to understand the Indian summer and northeast monsoons. However, the dynamics and characterization of winter precipitation is not well understood except with reference to the western disturbances (WDs). In this study, wintertime dynamics associated with large-scale flows and WDs influencing winter precipitation is proposed and termed 'Indian winter monsoon'. In addition, winter precipitation - the Indian winter monsoon - is proposed as eastward traveling WDs embedded in the large-scale subtropical westerlies over the Indian sub-continent. During winter (December, January and February) upper level subtropical westerly jet moves southwards and passes over the Indian sub-continent and provides associated precipitation over the northern Indian region. With concurrent research and changing global context, increased understanding of the Indian winter monsoon is imperative. Equally important is the behavior of WDs showing different patterns in the Peninsular India and the Himalaya particularly during the Holocene. During the Little Ice Age (LIA), it appears that high frequency of El Niño events was responsible for drier conditions in the core monsoon zone but generated more monsoon “breaks” over the Himalaya and thus the climatic conditions in the core Indian summer monsoon area were generally opposite to those in the foothills of the Himalaya during the Holocene period. During this period, a higher frequency of El Niño events might have restricted transport of warm water to the North Atlantic Ocean and brought about a cooling of adjacent continents including Central Asia and this may have amplified the extent of snow over Asia during the winter, and may even have been accounted for early snow in the region at the expanse of reduction in the Indian summer monsoon strength. Thus, this study delineates the Indian winter monsoon at intraseasonal-sub seasonal-interannual-paleoclimate scale and provides comprehensive details on defining the Indian winter monsoon and makes an attempt to understand the WDs particularly from mid-Holocene onwards as well.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Earth-Science Reviews - Volume 163, December 2016, Pages 297-322
نویسندگان
, , , , ,