A Hydroclimatological Analysis of Precipitation in the Ganges–Brahmaputra–Meghna River Basin

dc.contributor.authorCurtis, Scotten
dc.contributor.authorCrawford, Thomas W.en
dc.contributor.authorRahman, Munshi Khaleduren
dc.contributor.authorPaul, Bimal Kantien
dc.contributor.authorMiah, Md. Giashuddinen
dc.contributor.authorIslam, Md Sarifulen
dc.contributor.authorPatel, Mohinen
dc.contributor.departmentGeographyen
dc.date.accessioned2018-10-31T16:58:19Zen
dc.date.available2018-10-31T16:58:19Zen
dc.date.issued2018-09-29en
dc.date.updated2018-10-31T15:26:20Zen
dc.description.abstractUnderstanding seasonal precipitation input into river basins is important for linking large-scale climate drivers with societal water resources and the occurrence of hydrologic hazards such as floods and riverbank erosion. Using satellite data at 0.25-degree resolution, spatial patterns of monsoon (June-July-August-September) precipitation variability between 1983 and 2015 within the Ganges–Brahmaputra–Meghna (GBM) river basin are analyzed with Principal Component (PC) analysis and the first three modes (PC1, PC2 and PC3) are related to global atmospheric-oceanic fields. PC1 explains 88.7% of the variance in monsoonal precipitation and resembles climatology with the center of action over Bangladesh. The eigenvector coefficients show a downward trend consistent with studies reporting a recent decline in monsoon rainfall, but little interannual variability. PC2 explains 2.9% of the variance and shows rainfall maxima to the far western and eastern portions of the basin. PC2 has an apparent decadal cycle and surface and upper-air atmospheric height fields suggest the pattern could be forced by tropical South Atlantic heating and a Rossby wave train stemming from the North Atlantic, consistent with previous studies. Finally, PC3 explains 1.5% of the variance and has high spatial variability. The distribution of precipitation is somewhat zonal, with highest values at the southern border and at the Himalayan ridge. There is strong interannual variability associated with PC3, related to the El Nino/Southern Oscillation (ENSO). Next, we perform a hydroclimatological downscaling, as precipitation attributed to the three PCs was averaged over the Pfafstetter level-04 sub-basins obtained from the World Wildlife Fund (Gland, Switzerland). While PC1 was the principal contributor of rainfall for all sub-basins, PC2 contributed the most to rainfall in the western Ganges sub-basin (4524) and PC3 contributed the most to the rainfall in the northern Brahmaputra (4529). Monsoon rainfall within these two sub-basins were the only ones to show a significant relationship (negative) with ENSO, whereas four of the eight sub-basins had a significant relationship (positive) with sea surface temperature (SST) anomalies in the tropical South Atlantic. This work demonstrates a geographic dependence on climate teleconnections in the GBM that deserves further study.en
dc.description.versionPublished versionen
dc.format.mimetypeapplication/pdfen
dc.identifier.citationCurtis, S.; Crawford, T.; Rahman, M.; Paul, B.; Miah, M.G.; Islam, M.R.; Patel, M. A Hydroclimatological Analysis of Precipitation in the Ganges–Brahmaputra–Meghna River Basin. Water 2018, 10, 1359.en
dc.identifier.doihttps://doi.org/10.3390/w10101359en
dc.identifier.urihttp://hdl.handle.net/10919/85601en
dc.language.isoenen
dc.publisherMDPIen
dc.rightsCreative Commons Attribution 4.0 Internationalen
dc.rights.urihttp://creativecommons.org/licenses/by/4.0/en
dc.subjectmonsoonen
dc.subjectprecipitationen
dc.subjectENSOen
dc.subjecthydroclimateen
dc.subjectGangesen
dc.subjectBrahmaputraen
dc.subjectMeghnaen
dc.subjectriver basinen
dc.titleA Hydroclimatological Analysis of Precipitation in the Ganges–Brahmaputra–Meghna River Basinen
dc.title.serialWateren
dc.typeArticle - Refereeden
dc.type.dcmitypeTexten

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
water-10-01359.pdf
Size:
3.6 MB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 1 of 1
Name:
license.txt
Size:
1.5 KB
Format:
Item-specific license agreed upon to submission
Description: