Search Results

You are looking at 11 - 20 of 1,684 items for :

  • Weather modification x
  • Journal of Climate x
  • User-accessible content x
Clear All
K. Y. Li, M. T. Coe, and N. Ramankutty

) Weather generator Daily or hourly weather data are normally required by physically based land surface models. However, these data are not readily available in many regions, especially for long historical records. IBIS generates daily and hourly weather from monthly weather data using a stochastic weather generator as developed by Richardson and Wright (1984) , Richardson (1981) , and Geng et al. (1985) . The hourly data are generated from daily data. Hourly air temperature and humidity are

Full access
Gonéri Le Cozannet, Sophie Lecacheux, Etienne Delvallee, Nicolas Desramaut, Carlos Oliveros, and Rodrigo Pedreros

various teleconnection patterns are presented in section 3 and discussed in section 4 . In section 5 , the results are summarized and their ability to answer the questions raised in the introduction is discussed. 2. Data and methods a. Wave data This study uses the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40; Uppala et al. 2005 ), where the winds at 10 m above sea level were used to model sea-wave parameters from September 1958 to August 2002 ( Sterl and

Full access
K. Goubanova, L. Li, P. Yiou, and F. Codron

is due to the modification of regimes. We have shown that the weather regime patterns do not change in the future. We now verify how their occurrence frequencies change. Table 2 illustrates the change in the frequency of occurrence between present and future climate. The significance of the change was estimated using bootstrap method. 1 Only the change in the frequency of the blocking regime is significant at the 10% level. To evaluate which part of the total change in local winter temperature

Full access
Weihong Qian, Lingshen Quan, and Shaoyin Shi

1. Introduction It is only in the last three decades that the dimension and relevance of the dust storm phenomenon in arid and semiarid areas has been realized. Environmental consequences range from excessive soil mass and nutrient loss in source areas to pedological effects in deposition area air pollution and meso- to macroscale climatic modification ( Goudie 1983 ; Pye 1987 ; Littmann and Steinrucke 1989 ; Littmann 1991 ; Goudie and Middleton 1992 ). In the 1970s, it was identified that

Full access
A. A. Tsonis and J. B. Elsner

As Dr. Steppeler states in the beginning of his paper ( Steppeler 1997 ), infinite dimensional spatially extended systems that are described by a set of partial differential equations may often contain subsystems characterized by a much smaller dimensionality. Back in 1989, Tsonis and Elsner in an endeavor to explain the different estimated dimensions in weather and climate suggested the idea of subsystems in the climate system that operate at different space and/or time scales. Lorenz (1991

Full access
David E. Atkinson and K. Gajewski

-term stations and his own experience to subjectively modify isotherms to depict cooler ice field/upland regions. Alt and Maxwell (1990) employed nonstandard, short-term weather observation data from several, more recent sources (e.g., Atkinson et al. 2000 ) to increase spatial detail of a July temperature normal plot for the Queen Elizabeth Islands. Jacobs (1990) linked an automatic weather station to MSC weather stations using transfer functions allowing the generation of data at a “virtual” station

Full access
Xiaogu Zheng, Hisashi Nakamura, and James A. Renwick

1. Introduction Monthly and seasonal mean time series of meteorological variables are widely used for analyzing interannual climate variability and predictability, using either observed time series or the output of general circulation models (GCMs). Studies of predictability and potential predictability are usually based upon decomposition of temporal variability into a part called the “weather noise” variability that is fundamentally unpredictable on seasonal timescales and another part

Full access
F. Guichard, D. Parsons, and E. Miller

wants to get a complete picture of the problem on a global scale. Weather forecast models, which directly ingest sounding data in their analysis, should exhibit a sensitivity to this sudden moisture increase if the sounding data are not rejected in the data assimilation processes. In particular, many existing convective schemes assume a CAPE closure, relating the intensity of convection to the rate of CAPE variation. In regard to the large CAPE modification, this correction should significantly

Full access
K. J. Tory, S. S. Chand, J. L. McBride, H. Ye, and R. A. Dare

the stretching and shearing deformation, respectively, where u and υ are the zonal and meridional horizontal wind components, respectively. A detailed assessment of the detection method performance [applied to 20 yr of European Centre for Medium-Range Weather Forecasts (ECMWF) Interim Re-Analysis (ERA-Interim) data and verified against observed TCs] is given in Tory et al. (2013a) . This performance is summarized in the first row of Table 1 . The authors note that no detection method is

Full access
D. Lohar and B. Pal

decreases, which is an essential criterion for the formation of premonsoonthunderstorms, that is, northwesters. So, the increased vegetation or soil moisture is not always likely to increaserainfall activity; rather, mesoscale effects may be more important in some specific areas.1. Introduction Inadvertent modification of weather and climatethrough changes in land use has become a point ofgreat concern among the environmental scientiststhroughout the world. Changes in weather and climateas a result

Full access