@Article{VenturiniBaCaPeBeSc:2018:MeReTe,
author = "Venturini, Mateus S. and Bageston, Jos{\'e} Valentin and Caetano,
Nattan R. and Peres, Lucas V. and Bencherif, Hassan and Schuch,
Nelson Jorge",
affiliation = "{Universidade Federal de Santa Maria (UFSM)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Universidade Federal
de Santa Maria (UFSM)} and {Universidade Federal do Oeste do
Par{\'a}} and {Universit{\'e} de La R{\'e}union} and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "Mesopause region temperature variability and its trend in southern
Brazil",
journal = "Annales Geophysicae",
year = "2018",
volume = "36",
number = "2",
pages = "301--310",
month = "Mar.",
keywords = "Atmospheric composition and structure (middle atmosphere -
composition and chemistry, pressure density and temperature),
meteorology and atmospheric dynamics (climatology).",
abstract = "Nowadays, the study of the upper atmosphere is increasing, mostly
because of the need to understand the patterns of Earth's
atmosphere. Since studies on global warming have become very
important for the development of new technologies, understanding
all regions of the atmosphere becomes an unavoidable task. In this
paper, we aim to analyze the temperature variability and its trend
in the mesosphere and lower thermosphere (MLT) region during a
period of 12 years (from 2003 to 2014). For this purpose, three
different heights, i.e., 85, 90 and 95 km, were focused on in
order to investigate the upper atmosphere, and a geographic region
different to other studies was chosen, in the southern region of
Brazil, centered in the city of Santa Maria, RS (29 degrees 4'02
'' S; 53 degrees 48'25 '' W). In order to reach the objectives of
this work, temperature data from the SABER instrument (Sounding of
the Atmosphere using Broadband Emission Radiometry), aboard NASA's
Thermosphere Ionosphere Mesosphere Energetics Dynamics (TIMED)
satellite, were used. Finally, two cases were studied related to
distinct grids of latitude/longitude used to obtain the mean
temperature profiles. The first case considered a grid of 20
degrees x 20 degrees lat/long, centered in Santa Maria, RS,
Brazil. In the second case, the region was reduced to a size of 15
degrees x 15 degrees in order to compare the results and discuss
the two cases in terms of differences or similarities in
temperature trends. Observations show that the size of the
geographical area used for the average temperature profiles can
influence the results of variability and trend of the temperature.
In addition, reducing the time duration of analyses from 24 to 12
h a day also influences the trend significantly. For the smaller
ge-ographical region (15 degrees x 15 degrees) and the 12 h daily
time window (09:00-21:00 UT) it was found that the main
contributions for the temperature variability at the three heights
were the annual and semi-annual cycles and the solar flux
influence. A smaller trend (-0.02 +/- 0.16% decade(-1)) was found
at 90 km height and small positive trends (0.58 +/- 0.26% and 0.41
+/- 0.19% decade(-1)) were found at altitudes of 85 and 95 km,
respectively.",
doi = "10.5194/angeo-36-301-2018",
url = "http://dx.doi.org/10.5194/angeo-36-301-2018",
issn = "0992-7689",
language = "en",
targetfile = "venturini_mesopause.pdf",
urlaccessdate = "27 abr. 2024"
}