A note on the spatial structure of the covariability of observed Northern Hemisphere surface air temperatures

Elsner, James B.; Tsonis, Anastasios A.

doi:10.1007/bf00876893

Cited by 3 publications

(2 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2. By spectrally decomposing 100 randomly generated surrogate rainfall data matrices, we choose the fifth largest eigenvalue for each mode to represent the 95% significance level (Overland and Presendorfer 1982;Elsner and Tsonis 1991). This significance level, which is based on the assumption of white noise, is shown as the dashed line in Fig.…”

Section: Regionalizationmentioning

confidence: 99%

A Statistical Method for Forecasting Rainfall over Puerto Rico

Carter

Elsner

1997

Wea. Forecasting

Self Cite

View full text Add to dashboard Cite

Using results from a factor analysis regionalization of nontropical storm convective rainfall over the island of Puerto Rico, a statistical methodology is investigated for its potential to forecast rain events over limited areas. Island regionalization is performed on a 15-yr dataset, while the predictive model is derived from 3 yr of surface and rainfall data. The work is an initial attempt at improving objective guidance for operational rainfall forecasting in Puerto Rico. Surface data from two first-order stations are used as input to a partially adaptive classification tree to predict the occurrence of heavy rain. Results from a case study show that the methodology has skill above climatology-the leading contender in such cases. The algorithm also achieves skill over persistence. Comparisons of forecast skill with a linear discriminant analysis suggest that classification trees are an easier and more natural way to handle this kind of forecast problem. Synthesis of results confirms the notion that despite the very local nature of tropical convection, synoptic-scale disturbances are responsible for prepping the environment for rainfall. Generalizations of the findings and a discussion of a more realistic forecast setting in which to apply the technology for improving tropical rainfall forecasts are given.

show abstract

Section: Regionalizationmentioning

confidence: 99%

A Statistical Method for Forecasting Rainfall over Puerto Rico

Carter

Elsner

1997

Wea. Forecasting

Self Cite

View full text Add to dashboard Cite

show abstract

“…Then, as was done with the original data, the spectrum of surrogate eigenvalues is determined (Asw) from the matrix Csm = Rsm -Wsw. Repeating the entire procedure 100 times gives us a distribution of surrogate eigenvalues, and the magnitude of the fifth largest eigenvalue for each mode is chosen as the 95 percent significance level (Overland and Presendorfer, 1982;Elsner and Tsonis, 1991).…”

Section: Upper Bound On the Number Of Factorsmentioning

confidence: 99%

Convective Rainfall Regions of Puerto Rico

Carter

Elsner

1996

Int. J. Climatol.

Self Cite

View full text Add to dashboard Cite

Geographical regions of covariability in hourly precipitation over the island of Puerto Rico are exposed using factor analysis. It is argued that the data are consistent with a common factor model when an orthgonal rotation is applied to the factor loading matrix. The results suggest that Puerto Rico can be divided into six regions, with each region having a similar covariance structure of summer season convective rainfall. The six regions can be grouped into a western area and an eastern area based on contrasting diurnal rainfall signatures. The study is the first step in developing improved forecast guidance for precipitation over the island. It is believed to be one of the first studies attempting geographical regionalization of precipitation on the convective scale.

show abstract

Assessing the ability of the Köppen System to delineate the general world pattern of climates

Triantafyllou¹,

Tsonis²

1994

Geophysical Research Letters

Self Cite

View full text Add to dashboard Cite

The Köppen climate classification system [Köppen, 1923] is a scheme that provides an objective numerical basis for defining regional climatic types based on temperature and precipitation. Through the years it has been used as a scientific and teaching tool for prescribing the general world pattern of climates. Here for the first time an evaluation of the system is performed by employing coextensive temperature and precipitation data over the N. Hemisphere for the last 140 years. First the global pattern of climate type sensitivity is obtained. From this pattern it is discovered that several climate types exhibit a rather strong variability. Since all climate types depend on temperature we then tested whether or not the above variability is due to the fact that over the last 140 years the global climate system exhibits a well documented positive temperature trend known as global warming. We found that the Köppen system is rather insensitive to the observed global warming and concluded that overall the system performs rather poorly over Europe and Asia whereas it appears adequate over N. America and N. Africa.

show abstract

A note on the spatial structure of the covariability of observed Northern Hemisphere surface air temperatures

Cited by 3 publications

References 15 publications

A Statistical Method for Forecasting Rainfall over Puerto Rico

A Statistical Method for Forecasting Rainfall over Puerto Rico

Convective Rainfall Regions of Puerto Rico

Assessing the ability of the Köppen System to delineate the general world pattern of climates

Contact Info

Product

Resources

About