Analysing changes to the spatial structures of precipitation and temperature under different ENSO phases in the Southeast and Midwest United States

Meteorological applications

article

Won-Ho Nam¹  Guillermo A. Baigorria² 

[1] National Drought Mitigation Center, University of Nebraska-Lincoln;School of Natural Resources, University of Nebraska-Lincoln;Department of Agronomy & Horticulture, University of Nebraska-Lincoln

关键词: weather generator;    correlation matrix;    spatial structure;    ENSO;    precipitation;    temperature;   

DOI  :  10.1002/met.1526

学科分类：社会科学、人文和艺术（综合）

来源: Wiley

【 摘 要 】

The widespread influence of El Niño-Southern Oscillation (ENSO) phases on regional climate is well known to contribute to climate anomalies around the world. Understanding the effects of climate variability given the ENSO phases is an important component to improve crop management and reduce climate risk due to potential changes in temperature and precipitation patterns. Recognizing the spatial structure in precipitation and temperature under different ENSO phases is fundamental for comprehensive environmental assessments through decisions and policies that consider climate variability at regional scales. The objective of this study was to investigate if there is evidence of changes to the spatial structure of precipitation and temperature associated with the three categories of ENSO phases: El Niño, La Niña and neutral years in two study areas, the Southeast (Alabama, Florida and Georgia) and the Midwest (Nebraska) United States. Daily data of maximum temperature, minimum temperatures and precipitation (1981–2010) from 407 weather stations were analysed. The spatial structure was measured by analysing the monthly correlation matrices calculated from daily observations. To determine the potential changes to spatial structures of precipitation and temperature, the spatial structure was compared with using the complete 30 year period divided by the three categories of the ENSO phases. The results showed statistically significant differences in the spatial structures of maximum and minimum temperature and precipitation (amount and distribution) among the different ENSO phases and between the combinations of two kinds of different ENSO phases. Statistically significant changes in spatial correlation at seasonal and monthly timescales among the different ENSO phases were also observed in both regions. The statistical differences were not uniform in both regions, and some region-variable-month combinations showed no significance. Knowledge of spatial structure among some combinations of different ENSO phases at each region would be useful to improve further applications of weather/climate data in other disciplines such as geo-spatial weather generator.

【 授权许可】

CC BY|CC BY-NC|CC BY-NC-ND