TITLE:
Towards a Link between Climate Extremes and Thermodynamic Patterns in the City of Rio de Janeiro-Brazil: Climatological Aspects and Identified Changes
AUTHORS:
Wanderson Luiz-Silva, Fabricio Polifke da Silva, Claudine Pereira Dereczynski, José Ricardo de Almeida França
KEYWORDS:
Climate Change, Climatology, Instability Indices, Precipitation Extremes, Temperature Extremes
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.11 No.8,
August
28,
2023
ABSTRACT: Modification signs in extreme weather events may be directly related to
alterations in the thermodynamic panorama of the atmosphere that need to be
better understood. This study aimed to make a first interconnection between
climate extremes and thermodynamic patterns in the city of Rio de Janeiro. Maximum and minimum air temperature and
precipitation extreme indices from
two surface meteorological stations (ABOV and STCZ) and instability indices
based on temperature and humidity from radiosonde observations (SBGL) were
employed to investigate changes in the periods 1964-1980 (P1), 1981-2000
(P2), and 2001-2020 (P3). Statistical tests were
adopted to determine the significance and magnitude of trends. The
frequency of warm (cold) days and warm
(cold) nights are increasing (decreasing) in the city. Cold (Warm) extremes
are changing with greater magnitude in ABOV (STCZ) than in STCZ (ABOV). In
ABOV, there is a significant increase of +84 mm/decade in the rainfall
volume associated with severe precipitation (above the 95th percentile) and most extreme precipitation indices show an increase in
frequency and intensity. In STCZ, there is a decrease in extreme
precipitation until the 1990s, and from there, an increase, showing a wetter
climate in the most recent years. It is
also verified in SBGL that there is a statistically significant increase (decrease) in air temperature of +0.1°C/decade (-0.2°C/decade) and relative humidity of +1.2%/decade (-3%/decade) at the low and middle (high)
troposphere. There is a visible rising trend in most of the evaluated
instability indices over the last few decades. The increasing trends of some
extreme precipitation indices are probably allied to the precipitable water
increasing trend of +1.2 mm/decade.