Dataset Information

Influence of Land Cover and Soil Moisture based Brown Ocean Effect on an Extreme Rainfall Event from a Louisiana Gulf Coast Tropical System.

ABSTRACT: Extreme flooding over southern Louisiana in mid-August of 2016 resulted from an unusual tropical low that formed and intensified over land. We used numerical experiments to highlight the role of the 'Brown Ocean' effect (where saturated soils function similar to a warm ocean surface) on intensification and it's modulation by land cover change. A numerical modeling experiment that successfully captured the flood event (control) was modified to alter moisture availability by converting wetlands to open water, wet croplands, and dry croplands. Storm evolution in the control experiment with wet antecedent soils most resembles tropical lows that form and intensify over oceans. Irrespective of soil moisture conditions, conversion of wetlands to croplands reduced storm intensity, and also, non-saturated soils reduced rain by 20% and caused shorter durations of high intensity wind conditions. Developing agricultural croplands and more so restoring wetlands and not converting them into open water can impede intensification of tropical systems that affect the area.

SUBMITTER: Nair US

PROVIDER: S-EPMC6868174 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Influence of Land Cover and Soil Moisture based Brown Ocean Effect on an Extreme Rainfall Event from a Louisiana Gulf Coast Tropical System.

Nair Udaysankar S US Rappin Eric E Foshee Emily E Smith Warren W Pielke Roger A RA Mahmood Rezaul R Case Jonathan L JL Blankenship Clay B CB Shepherd Marshall M Santanello Joseph A JA Niyogi Dev D

Scientific reports 20191120 1

Extreme flooding over southern Louisiana in mid-August of 2016 resulted from an unusual tropical low that formed and intensified over land. We used numerical experiments to highlight the role of the 'Brown Ocean' effect (where saturated soils function similar to a warm ocean surface) on intensification and it's modulation by land cover change. A numerical modeling experiment that successfully captured the flood event (control) was modified to alter moisture availability by converting wetlands to ...[more]

PMID: 31748625

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Dataset Information

Influence of Land Cover and Soil Moisture based Brown Ocean Effect on an Extreme Rainfall Event from a Louisiana Gulf Coast Tropical System.

Publications

Influence of Land Cover and Soil Moisture based Brown Ocean Effect on an Extreme Rainfall Event from a Louisiana Gulf Coast Tropical System.

Similar Datasets

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