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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Stratification and mixing in large floodplain lakes along the lower Amazon River

Texto completo
Autor(es):
Augusto-Silva, Petala Bianchi [1] ; MacIntyre, Sally [2, 3] ; Rudorff, Conrado de Moraes [4] ; Cortes, Alicia [3] ; Melack, John Michael [2, 3]
Número total de Autores: 5
Afiliação do(s) autor(es):
[1] Natl Inst Space Res INPE, Dept Remote Sensing, Sao Jose Dos Campos, SP - Brazil
[2] Univ Calif Santa Barbara, Dept Ecol Evolut & Marine Biol, Santa Barbara, CA 93106 - USA
[3] Univ Calif Santa Barbara, Inst Marine Sci, Santa Barbara, CA 93106 - USA
[4] Ctr Nacl Monitoramento & Alerta Desastres Nat CEM, Sao Jose Dos Campos, SP - Brazil
Número total de Afiliações: 4
Tipo de documento: Artigo Científico
Fonte: JOURNAL OF GREAT LAKES RESEARCH; v. 45, n. 1, p. 61-72, FEB 2019.
Citações Web of Science: 5
Resumo

Large, shallow lakes are common in the extensive floodplains throughout the tropics. To determine controls on their mixing dynamics, we instrumented 5 stations in two shallow, connected tropical lakes on the lower Amazon floodplain with meteorological and temperature sensors. A tight relation between changes in thermal structure and L-MO/h (the ratio of the Monin-Obukhov length scale to the depth of the actively mixing layer) indicates the sensitivity of thermal structure to wind speed relative to heating and cooling. Four regimes led to variations in mixing: (i) high solar radiation with light winds in the mid-morning to early afternoon resulted in shallow stratification, 0<L-MO/h<1;(ii) afternoons with higher winds caused the diurnal thermocline to downwell and heat to mix to deeper layers, L-MO/h;(iii) by late afternoon, buoyancy flux became negative and L-MO/h < -1 and with u({*}w), and w({*}) both >0.06 m s(-1), mixing from wind and cooling co-occurred; and (iv) convection dominated mixing on nights with light winds, -1 < L-MO/h <0. Pattern (ii) occurred mid-day if winds were higher. When winds were intermittent and regime (i) predominated mid-day, changes in heat content were primarily determined by one dimensional processes of heating and cooling. When easterly winds were sustained and regime (ii) occurred mid-day, heat was transported west in the day, and colder water upwelled to the west or was advected to the west and north at night. Subtle differences in wind speed determined the extent to which advection moderated the thermal structure. (C) 2018 International Association for Great Lakes Research. Published by Elsevier B.V. All rights reserved. (AU)

Processo FAPESP: 11/23594-8 - Sensoriamento remoto aplicado à modelagem de impactos antropogênicos sobre propriedades ecológicas de ambientes alagáveis e aquáticos da planície do Solimões/Amazonas
Beneficiário:Evlyn Márcia Leão de Moraes Novo
Linha de fomento: Auxílio à Pesquisa - Regular