@InProceedings{BotiaGerMarFisLav:2018:TrNiMe,
author = "Botia, Santiago and Gerbig, Christoph and Marshall, Julia and
Fisch, Gilberto and Lavric, Jost Valentin",
affiliation = "{Max Planck Institute for Biogeochemistry} and {Max Planck
Institute for Biogeochemistry} and {Max Planck Institute for
Biogeochemistry} and {Instituto Nacional de Pesquisas Espaciais
(INPE)} and {Max Planck Institute for Biogeochemistry}",
title = "Tracking Nighttime Methane Signals at the Amazon Tall Tower
Observatory (ATTO)",
year = "2018",
organization = "AGU Fall Meeting",
abstract = "During the last decades global methane growth rate has been
variable with a stabilization period between 1999-2006, and a
steady increase since 2007. The most important individual source
of methane globally are wetlands, which in the Amazon rainforest
are abundant. Wetland emissions in the Amazon represent 15% of the
global wetland emissions. Therefore, understanding the main
drivers of methane emissions in this region is vital to constrain
its global variability. At the Amazon Tall Tower Observatory
(ATTO), an unprecedented 6-year record of methane concentrations
at half-hourly intervals provides a unique opportunity to
understand methane variability at different temporal scales.
Methane concentrations show a seasonal pattern at all 5
measurement levels, with a peak during the dry season.
Interestingly, the maximum values are found at the highest
measurement inlet (80m). Our data record shows that for some years
this dry season peak is mainly driven by a nighttime methane
enhancement at the highest level, when the nocturnal boundary
layer is under stable conditions and there is almost a complete
absence of vertical mixing. Here we present a detailed analysis of
the atmospheric conditions within and above the canopy for this
nighttime methane enhancement, showing that the main process
responsible for the majority of vertical exchange is intermittent
turbulence; a characteristic of the nocturnal boundary layer in
the Amazon. In addition, we provide a footprint analysis to derive
the source of this nocturnal methane by using high-resolution
atmospheric modeling (WRF-STILT). Preliminary results show that
this footprint could vary from 80 to 150 km, when the predominant
wind is from the northeast.",
conference-location = "Washington, D. C.",
conference-year = "10-14 dec.",
language = "en",
targetfile = "botia_tracking.pdf",
urlaccessdate = "11 maio 2024"
}