P1.23 Downscaling and Projection of the Wintertime Extreme Daily Precipitation over North America by Large-scale Atmospheric Circulation
نویسندگان
چکیده
The influence of large scale circulation, represented by the first three rotated EOFs and their associated PCs of wintertime mean sea level pressure, on winter maximum daily precipitation over the North America during 1948-1998 has been investigated. The observed relationship between the circulation and the extreme precipitation is then used to derive projected changes in extreme precipitation in the future due to circulation change caused by the increase of greenhouse gases as simulated by CGCM2 conducted at CCCma forced by IPCC “IS92a” forcing scenario. It appears that impact of human induced circulation change on winter maximum daily precipitation in 2050-2099 is comparable to the observed response of extremes precipitation to the occurrence of El Nino in the second half of the 20 century. ∗ Corresponding author address: Dr. Xuebin Zhang, Climate Research Branch, Meteorological Service of Canada, 4905 Dufferin Street, Downsview, Ontario, Canada, M3H 5T4 ; E-mail: [email protected]
منابع مشابه
Study of the models of large-scale atmospheric circulation system model on intesify rainfall in Ardebil plain
Atmospheric circulation is important to determine the surface climate and environment, and affect regional climate and surface features. In this study, to quantify its effect, the classification system, developed by Lamb is applied to obtain circulation information for Ardabil, North West Province in Iran, on a daily basis, and is a method to classify synoptic weather for study area. For that p...
متن کاملتبیین علل کاهش یافتن مقدار و شدت بارشهای زمستانه در قیاس با بارشهای پاییزه در سواحل جنوبی دریای خزر
The causes of wintertime precipitation decrease in the Southern Coast of Caspian Sea (SCCS) compared to its counterpart in autumn, is investigated with the use of synoptic stations daily dataset of SCCS and gridded NCEP/NCAR and NOAA dataset. The structure of atmospheric circulation and synoptic and physical conditions over the Caspian Sea region which are dominate in the winter and autumn prec...
متن کاملEvaluation of the performance of the CMIP5 General Circulation Models in predicting the Indian Ocean Monsoon precipitation over south Sistan and Baluchestan, using the past hydrological changes in the region
1-Introduction Climate change refers to any significant change in the existing mean climatic conditions within a certain time period (Jana and Majumder, 2010; Giorgi, 2006). Earth's climate change through history has happened (Nakicenovic et al., 2000; Bytnerowicz et al., 2007). 2-Materials and methods In this study, daily precipitation and daily maximum (Tmax) and daily minimum (Tmin) tempera...
متن کاملProbabilistic Projections of Climate Change for the Mid-Atlantic Region of the United States: Validation of Precipitation Downscaling during the Historical Era*
This study uses a statistical downscaling method based on self-organizing maps (SOMs) to produce highresolution, downscaled precipitation estimates over the state of Pennsylvania in the mid-Atlantic region of the United States. The SOMs approach derives a transfer function between large-scale mean atmospheric states and local meteorological variables (daily point precipitation values) of intere...
متن کاملInvestigation of the atmospheric circulation anomalies associated with extreme rainfall events over the Coastal West Africa
This study investigates the atmospheric circulation associated with extreme rainfall events over the coastal West Africa. The rainfall data of this study were obtained from the Global Precipitation Climatology Centre (GPCC), spanning from 1981 to 2010. The atmospheric datasets were also obtained from the ERA-Interim reanalysis. The study employed the Z-Index to categorize dry and wet years into...
متن کامل