Climatic fluctuations and homogenization of Northeast Brazil using precipitation data
Autor(a) principal: | |
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Data de Publicação: | 2014 |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Pesquisa Agropecuária Brasileira (Online) |
Texto Completo: | https://seer.sct.embrapa.br/index.php/pab/article/view/15593 |
Resumo: | In order to assess the cyclic variations in the precipitation series and to homogenize the precipitation regimes of the Northeast Brazil 70-years annual precipitation data of 105-locations were subjected to power spectrum analysis. In terms of some cycles the regions above and below 8°S lat differ significantly. Also regions between 4-8°S lat. are different in some respects from regions above 4°S lat. This is true with respect to coefficient of variation of annual precipitation. The auto-regression of Fortaleza data of 1849 to 1981 revealed the presence of four cycles, namely 52, 26,13 and 6.5 years, The integrated curve of these four cycles is compared with the observed precipitation. The agreement in general is good with few exceptions. The same predicted curve is also used to compare with the observed precipitation at few other locations. The agreement is good only for few regions. The coefficient of variation of annual precipitation presented a non-homogeneity over regions above 8°S lat. compared to regions below 8°S lat. This is also true even with the observed cycles. This type of discrepancy is attributed to the non-homogeneity in the data series, which is also substantiated with few examples. This study demonstrates that the basic precipitation data must be corrected for homogeneity before they are actually used in the agricultural productivity estimates or planning strategies using regression approach. |
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Climatic fluctuations and homogenization of Northeast Brazil using precipitation dataFlutuações climáticas e homogeneização do Nordeste do Brasil utilizando dados de precipitaçãocycles; power spectrumciclos; poder de espectroIn order to assess the cyclic variations in the precipitation series and to homogenize the precipitation regimes of the Northeast Brazil 70-years annual precipitation data of 105-locations were subjected to power spectrum analysis. In terms of some cycles the regions above and below 8°S lat differ significantly. Also regions between 4-8°S lat. are different in some respects from regions above 4°S lat. This is true with respect to coefficient of variation of annual precipitation. The auto-regression of Fortaleza data of 1849 to 1981 revealed the presence of four cycles, namely 52, 26,13 and 6.5 years, The integrated curve of these four cycles is compared with the observed precipitation. The agreement in general is good with few exceptions. The same predicted curve is also used to compare with the observed precipitation at few other locations. The agreement is good only for few regions. The coefficient of variation of annual precipitation presented a non-homogeneity over regions above 8°S lat. compared to regions below 8°S lat. This is also true even with the observed cycles. This type of discrepancy is attributed to the non-homogeneity in the data series, which is also substantiated with few examples. This study demonstrates that the basic precipitation data must be corrected for homogeneity before they are actually used in the agricultural productivity estimates or planning strategies using regression approach.Objetivando conhecer a variação cíclica nas séries de precipitação e homogeneidade do regime pluviométrico do Nordeste do Brasil, dados de 70 anos de precipitação anual de 105 locais foram submetidos a análise do poder de espectro. Em termos de alguns ciclos as regiões acima e abaixo de 8° de latitude diferem significativamente. Também regiões entre 4.8° de latitude são diferentes em relação as regiões acima de 4° de latitude em alguns aspectos. Isto certamente também é correto com relação ao coeficiente de variação da precipitação anual. A auto-regressão dos dados de Fortaleza de 1849 a 1981 indica a presença de quatro ciclos, normalmente de 52, 26, 13 e 6,5 anos. A curva integrada deste quatro ciclos é comparada com a precipitação observada. A precisão em geral é boa, com poucas exceções. A mesma curva estimada é também usada para comparar com precipitações observadas em outros locais. A precisão é boa somente para poucas regiões. O coeficiente de variação da precipitação anual apresenta uma não-homogeneidade sobre regiões acima de 8° da latitude comparado a regiões abaixo de 8° de latitude. Isto certamente também é correto. Este tipo de discrepância é atribuído à não-homogeneidade da série de dados, a qual é também evidenciada com poucos exemplos. Este estudo demonstra que os dados básicos de precipitação deve ser corretamente homogeneizado, antes de ser utilizado em estimativa de produtividade agrícola ou estratégias de planejamento, utilizando métodos de regressão.Pesquisa Agropecuaria BrasileiraPesquisa Agropecuária BrasileiraReddy, S. Jeevananda2014-04-16info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://seer.sct.embrapa.br/index.php/pab/article/view/15593Pesquisa Agropecuaria Brasileira; v.19, n.5, maio 1984; 529-543Pesquisa Agropecuária Brasileira; v.19, n.5, maio 1984; 529-5431678-39210100-104xreponame:Pesquisa Agropecuária Brasileira (Online)instname:Empresa Brasileira de Pesquisa Agropecuária (Embrapa)instacron:EMBRAPAenghttps://seer.sct.embrapa.br/index.php/pab/article/view/15593/9594info:eu-repo/semantics/openAccess2014-04-16T19:22:17Zoai:ojs.seer.sct.embrapa.br:article/15593Revistahttp://seer.sct.embrapa.br/index.php/pabPRIhttps://old.scielo.br/oai/scielo-oai.phppab@sct.embrapa.br || sct.pab@embrapa.br1678-39210100-204Xopendoar:2014-04-16T19:22:17Pesquisa Agropecuária Brasileira (Online) - Empresa Brasileira de Pesquisa Agropecuária (Embrapa)false |
dc.title.none.fl_str_mv |
Climatic fluctuations and homogenization of Northeast Brazil using precipitation data Flutuações climáticas e homogeneização do Nordeste do Brasil utilizando dados de precipitação |
title |
Climatic fluctuations and homogenization of Northeast Brazil using precipitation data |
spellingShingle |
Climatic fluctuations and homogenization of Northeast Brazil using precipitation data Reddy, S. Jeevananda cycles; power spectrum ciclos; poder de espectro |
title_short |
Climatic fluctuations and homogenization of Northeast Brazil using precipitation data |
title_full |
Climatic fluctuations and homogenization of Northeast Brazil using precipitation data |
title_fullStr |
Climatic fluctuations and homogenization of Northeast Brazil using precipitation data |
title_full_unstemmed |
Climatic fluctuations and homogenization of Northeast Brazil using precipitation data |
title_sort |
Climatic fluctuations and homogenization of Northeast Brazil using precipitation data |
author |
Reddy, S. Jeevananda |
author_facet |
Reddy, S. Jeevananda |
author_role |
author |
dc.contributor.none.fl_str_mv |
|
dc.contributor.author.fl_str_mv |
Reddy, S. Jeevananda |
dc.subject.por.fl_str_mv |
cycles; power spectrum ciclos; poder de espectro |
topic |
cycles; power spectrum ciclos; poder de espectro |
description |
In order to assess the cyclic variations in the precipitation series and to homogenize the precipitation regimes of the Northeast Brazil 70-years annual precipitation data of 105-locations were subjected to power spectrum analysis. In terms of some cycles the regions above and below 8°S lat differ significantly. Also regions between 4-8°S lat. are different in some respects from regions above 4°S lat. This is true with respect to coefficient of variation of annual precipitation. The auto-regression of Fortaleza data of 1849 to 1981 revealed the presence of four cycles, namely 52, 26,13 and 6.5 years, The integrated curve of these four cycles is compared with the observed precipitation. The agreement in general is good with few exceptions. The same predicted curve is also used to compare with the observed precipitation at few other locations. The agreement is good only for few regions. The coefficient of variation of annual precipitation presented a non-homogeneity over regions above 8°S lat. compared to regions below 8°S lat. This is also true even with the observed cycles. This type of discrepancy is attributed to the non-homogeneity in the data series, which is also substantiated with few examples. This study demonstrates that the basic precipitation data must be corrected for homogeneity before they are actually used in the agricultural productivity estimates or planning strategies using regression approach. |
publishDate |
2014 |
dc.date.none.fl_str_mv |
2014-04-16 |
dc.type.none.fl_str_mv |
|
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://seer.sct.embrapa.br/index.php/pab/article/view/15593 |
url |
https://seer.sct.embrapa.br/index.php/pab/article/view/15593 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
https://seer.sct.embrapa.br/index.php/pab/article/view/15593/9594 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Pesquisa Agropecuaria Brasileira Pesquisa Agropecuária Brasileira |
publisher.none.fl_str_mv |
Pesquisa Agropecuaria Brasileira Pesquisa Agropecuária Brasileira |
dc.source.none.fl_str_mv |
Pesquisa Agropecuaria Brasileira; v.19, n.5, maio 1984; 529-543 Pesquisa Agropecuária Brasileira; v.19, n.5, maio 1984; 529-543 1678-3921 0100-104x reponame:Pesquisa Agropecuária Brasileira (Online) instname:Empresa Brasileira de Pesquisa Agropecuária (Embrapa) instacron:EMBRAPA |
instname_str |
Empresa Brasileira de Pesquisa Agropecuária (Embrapa) |
instacron_str |
EMBRAPA |
institution |
EMBRAPA |
reponame_str |
Pesquisa Agropecuária Brasileira (Online) |
collection |
Pesquisa Agropecuária Brasileira (Online) |
repository.name.fl_str_mv |
Pesquisa Agropecuária Brasileira (Online) - Empresa Brasileira de Pesquisa Agropecuária (Embrapa) |
repository.mail.fl_str_mv |
pab@sct.embrapa.br || sct.pab@embrapa.br |
_version_ |
1793416699666497536 |