Search Results

You are looking at 121 - 130 of 1,717 items for :

  • Weather modification x
  • Journal of Climate x
  • Refine by Access: All Content x
Clear All
David I. Duncan, Christian D. Kummerow, and Gregory S. Elsaesser

1. Introduction Clouds, precipitation, and their effects on the local environment are inextricably linked, yet are often treated separately. New paradigms that seek to exploit the relationship between cloud and precipitation states offer some hope to link the two disciplines. Studies that have endeavored to categorize “weather states” have approached the issue from the perspective of either classifying similar cloud states (e.g., Jakob and Tselioudis 2003 ; Rossow et al. 2005 ) or

Full access
Harvey S. J. Hill, James W. Mjelde, Wesley Rosenthal, and Peter J. Lamb

information is obtained through the use of an economic decision model. Embedded within this decision model is a biophysical simulation model of sorghum growth that requires daily weather data. The site-level production is then aggregated by the number of hectares each site represents to obtain the aggregate sorghum supply curve. A similar aggregation approach is used to obtain the impacts on expected aggregate nitrogen use, costs, net returns, and planted hectares. a. The economic model To obtain the

Full access
D. Alex Burrows, Craig R. Ferguson, Matthew A. Campbell, Geng Xia, and Lance F. Bosart

1. Introduction The Great Plains (GP) low-level jet (LLJ) is the primary transport mechanism of moisture-laden air from the Gulf of Mexico into the GP and is essential to the region’s agricultural and wind energy sectors, hydroclimate, and severe weather regimes. Bonner (1968) first objectively defined the southerly GPLLJ based on its diurnal oscillation in speed, height, and direction. The GPLLJ has a well-defined corridor (Texas to South Dakota) with a diurnal cycle that peaks after local

Full access
Guomin Wang, Pandora Hope, Eun-Pa Lim, Harry H. Hendon, and Julie M Arblaster

1. Introduction Extreme weather and climate events are of great concern to the public, emergency services, industry, finance sectors, and policy makers. While there is strong evidence linking global-scale warming to the increases in anthropogenic greenhouse gas emissions ( Bindoff et al. 2013 ), there is increasing evidence that extreme heat and rainfall events are increasing as well. However, because of the smaller samples of extreme events, which by definition occur in the tails of

Restricted access
Roy Rasmussen, Changhai Liu, Kyoko Ikeda, David Gochis, David Yates, Fei Chen, Mukul Tewari, Michael Barlage, Jimy Dudhia, Wei Yu, Kathleen Miller, Kristi Arsenault, Vanda Grubišić, Greg Thompson, and Ethan Gutmann

simulations The Weather Research and Forecasting (WRF) regional weather and climate model version 3.0 ( Skamarock et al. 2005 ) was used for both the historical verification runs and the PGW simulations. The relevant model parameterizations included the Noah land surface model ( Chen and Dudhia 2001 ; Ek et al. 2003 ); Mellor–Yamada–Janjić (MYJ) planetary boundary layer scheme ( Skamarock et al. 2005 ); Community Atmosphere Model’s (CAM) longwave and shortwave schemes ( Collins et al. 2006 ); and

Full access
J. E. Kay, K. Raeder, A. Gettelman, and J. Anderson

describe and implement a physically motivated modification to the stratus cloud parameterization, requiring a well-mixed boundary layer for stratus clouds to be diagnosed. We then contrast the influence of stability-based cloud parameterizations on Arctic clouds in the forecasts and freely evolving CAM4 runs. In section 4 , we discuss the relevance of our findings for high-latitude climate feedbacks. We conclude with a summary of our most important findings in section 5 . 2. Model description and

Full access
Delphine Texier, Nathalie de Noblet, and Pascale Braconnot

the magnitude of monsoon changes was underestimated by models ( Yu and Harrison 1996 ; Texier et al. 1997 ; Joussaume et al. 1999 ). These results suggest that the 6-kyr-BP orbital change alone is not sufficient to produce the observed climate change;internal feedbacks must then be accounted for. Numerical experiments have shown that African and Asian summer monsoons, at present as well as during the mid-Holocene, are sensitive to modifications in the land surface consequent to changes in 1

Full access
Jeremy Chardon, Benoit Hingray, Anne-Catherine Favre, Philemon Autin, Joël Gailhard, Isabella Zin, and Charles Obled

meteorological variables (called the predictands). A large number of SDMs have been proposed over the last two decades [see Maraun et al. (2010) for a review]. They are widely used to generate weather scenarios for past or future climates from outputs of climate models (e.g., Wilby et al. 1999 ; Hanssen-Bauer et al. 2005 ; Boé et al. 2007 ; Lafaysse et al. 2014 ). They can also be used to reconstruct weather scenarios from atmospheric reanalysis data [specific events as in Auffray et al. (2011) or

Full access
Ole B. Christensen, Jens H. Christensen, Bennert Machenhauer, and Michael Botzet

of 19 km is driven by an RCM with a resolution of 57 km, which in turn is driven by a GCM that has a resolution of about 250 km (spectral T42). Experience from numerical weather prediction modeling shows that too big a difference in resolution between driving fields and an RCM gives numerical problems. Therefore the double nesting. We focus on the Scandinavian Peninsula where many finescale details in the topography are responsible for the local climate. At the high resolution used here, local

Full access
Maria K. Flatau, Piotr J. Flatau, and Daniel Rudnick

1. Introduction This paper discusses double monsoon onsets that are related to extremely harsh conditions in India: dry and hot weather ( Halpert et al. 1996 ) just before the real monsoon begins. There is fairly little known about multiple onset climatology, synoptics, or the relationship with the real onset and the mean monsoon circulation. The term “double” or “multiple” onset was apparently first used by Fieux and Stommel (1977) . They studied different types of onset of the southwest

Full access