Search Results

You are looking at 1 - 10 of 11 items for :

  • Regional effects x
  • U.S. CLIVAR Drought x
  • All content x
Clear All
Renu Joseph and Ning Zeng

converged on the relative importance of these processes ( Nemani et al. 2003 ). What is clear is that this cooling and drying is very different from typical ENSO response where warming accompanies drying ( Zeng et al. 2005 ). However, there are two regions (northern Australia and western South America) where NPP response is different from most other regions, indicating the competing effects of cooling and drying on NPP and R h are such that R h does not always dominate. We expect such regional

Full access
Matías Méndez and Víctor Magaña

socioeconomic perspective (e.g., García-Acosta et al. 2003 ; Magaña and Conde 2003 ). However, dry and wet episodes are also part of the natural climate variability in both central and southern Mexico. Regionally, prolonged dry periods in recent centuries have been analyzed based on documents (e.g., Endfield and Fernández-Tejedo 2006 ), meteorological records (e.g., Mendoza et al. 2005 ; Mendoza et al. 2006 ), and proxy climatic reconstructions, such as marine and lake core sediments ( Metcalfe and

Full access
Alfredo Ruiz-Barradas and Sumant Nigam

, the models used, the SST forcing, and an overview of the results. The hierarchy of interactions that give rise to precipitation variability within a model, that is, local land surface–atmosphere versus remote SST–moisture fluxes, plays a crucial role in the simulation of regional summer hydroclimate variability. Regional hydroclimate over the central United States strongly depends on the moisture transport from the Gulf of Mexico via the Great Plains low-level jet, particularly in the summer

Full access
Alfredo Ruiz-Barradas and Sumant Nigam

1. Introduction Global climate change due to increased man-induced greenhouse gases threatens societies and ecosystems around the planet. In the same way that climate is not equal everywhere, climate change will have different impacts around the globe. Thus, interest in regional climate change, especially hydroclimate, has increased. As a result of society’s dependence on water supply, as well as the need for prevention and mitigation of extreme hydroclimate events, current and projected

Full access
Caio A. S. Coelho and Lisa Goddard

others have looked at regional precipitation changes, but little has been done on how ENSO teleconnections—particularly El Niño–induced drought patterns—together with projected precipitation changes in the tropics can inform the changing risk of drought conditions. This study first evaluates the patterns, magnitude, and spatial extent of El Niño–induced tropical droughts during a control period in the twentieth century in climate simulations, which have realistic evolution of greenhouse gasses. Next

Full access
Bradfield Lyon

waves that often, though certainly not always, accompany them. For example, during the 1991/92 summer drought in southern Africa it is estimated that as much as 3 million tons of grain production were lost in this predominately rain-fed agricultural region ( Dilley and Heyman 1995 ). The extreme high temperatures that accompanied the drought not only contributed to the crop losses but also to widespread livestock mortality ( Sivakumar 2006 ) and stresses on regional water supplies. The joint

Full access
Philip J. Pegion and Arun Kumar

. Suarez , 2000 : An atlas of seasonal means simulated by the NSIPP 1 atmospheric GCM. Vol. 17. NASA Tech. Memo. 104606, Goddard Space Flight Center, Greenbelt, MD, 194 pp . Brohan , P. , J. J. Kennedy , I. Harris , S. F. B. Tett , and P. D. Jones , 2006 : Uncertainty estimates in regional and global observed temperature changes: A new dataset from 1850. J. Geophys. Res. , 111 , D12106 . doi:10.1029/2005JD006548 . Campana , K. , and P. Caplan , Eds. cited . 2009

Full access
Kingtse C. Mo, Jae-Kyung E. Schemm, and Soo-Hyun Yoo

1. Introduction Long-lasting drought has an enormous impact on the nation’s economy and society. Skillful drought prediction can mitigate devastating economic effects on people and ecosystems. To improve drought forecasts, one needs to understand the causes that trigger and sustain drought. Because drought implies prolonged rainfall and soil moisture deficits, they are often modulated by low-frequency sea surface temperature anomalies (SSTAs). In the Pacific, decadal trends of SSTAs in the

Full access
Antonietta Capotondi and Michael A. Alexander

and global SSTs in a 1360-yr-long control integration of the Parallel Climate Model, a fully coupled climate model. The focus of this study was on “megadroughts,” defined as 11-yr running mean regional area-averaged negative precipitation anomalies lasting for at least 20 yr. A statistically significant correlation was found between the low-frequency evolution of precipitation in the southwestern North America and low-frequency Pacific SST anomalies. The correlation pattern is very similar to the

Full access
Kirsten L. Findell and Thomas L. Delworth

for 37 years. The last 50 years are used when available; the last 36 years are used with the GFS results. All of the experiments discussed in this paper are run with prescribed SSTs. Thus, while these experiments provide clear insight into the way SST anomalies can alter regional climate properties, they overlook the interesting question of further feedbacks and coupling to the SST fields. Such a study would require a full dynamic coupled model with an interactive ocean, beyond the scope of the

Full access