Turbulence regimes in the nocturnal roughness sublayer: Interaction with deep convection and tree mortality in the Amazon
Journal Article
·
· Agricultural and Forest Meteorology
- Amazonian National Research Institute (INPA-CLIAMB), Manaus, AM (Brazil)
- Amazonian National Research Institute (INPA-CLIAMB), Manaus, AM (Brazil); Federal Institute of Pará (IFPA), Belém, PA (Brazil)
- Univ. of Oklahoma, Norman, OK (United States)
- Federal University of West Pará (UFOPA), Santarém, PA (Brazil)
- Universidade Federal do Pampa, Alegrete (Brazil)
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- National Institute for Spatial Research (INPE), Cachoeira Paulista, SP (Brazil)
- Max Planck Institute for Biogeochemistry, Jena (Germany)
We investigated the influence of seasonality and proximity to the forest canopy on nocturnal turbulence regimes in the roughness sublayer of a Central Amazon forest. Since convective systems of different scales are common in this region, we also analyzed the effect of extreme wind gusts (propagated from convective downdrafts) on the organization of the turbulence regimes, and their potential to cause the mortality of canopy trees. Our data include high-frequency winds, temperature and ozone concentration at different heights during the dry and wet seasons of 2014. In addition, we used critical wind-speed data derived from a tree-winching experiment and a modeling study conducted in the same study site. Two different turbulence regimes were identified at three heights above the canopy: a weakly stable (WS) and a very stable regime (VS). The threshold wind speeds that mark the transition between turbulence regimes were larger during the dry season and increased as a function of the height above the canopy. The turbulent fluxes of sensible heat and momentum during the WS accounted for 88% of the entire nighttime flux. Downdrafts occurred only in the WS and favored a fully coupled state of wind flow along the canopy profile. The destructive potential of winds was four times higher than on nights without downdrafts.
- Research Organization:
- ARM Data Center, Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC); USDOE Office of Science (SC), Biological and Environmental Research (BER)
- Grant/Contract Number:
- AC02-05CH11231; AC05-76RL01830
- OSTI ID:
- 1992474
- Alternate ID(s):
- OSTI ID: 2192731
- Journal Information:
- Agricultural and Forest Meteorology, Journal Name: Agricultural and Forest Meteorology Vol. 339; ISSN 0168-1923
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Daytime turbulent exchange between the Amazon forest and the atmosphere
Influence of nocturnal low‐level jet on turbulence structure and CO2 flux measurements over a forest canopy
Air turbulence characteristics at multiple sites in and above the Amazon rainforest canopy
Journal Article
·
Thu Sep 20 00:00:00 EDT 1990
· Journal of Geophysical Research; (USA)
·
OSTI ID:5937900
Influence of nocturnal low‐level jet on turbulence structure and CO2 flux measurements over a forest canopy
Journal Article
·
Tue May 20 00:00:00 EDT 2008
· Journal of Geophysical Research
·
OSTI ID:929556
Air turbulence characteristics at multiple sites in and above the Amazon rainforest canopy
Journal Article
·
Wed Jun 06 20:00:00 EDT 2018
· Agricultural and Forest Meteorology
·
OSTI ID:1611560