Banca de QUALIFICAÇÃO: LOURDES GABRIELA VIEIRA BATISTA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : LOURDES GABRIELA VIEIRA BATISTA
DATE: 09/07/2021
TIME: 09:00
LOCAL: VIDEOCONFERÊNCIA
TITLE:

FOG FORMATION PROCESSES IN EDUARDO GOMES AND PONT PELADA AIRFIELDS, IN MANAUS-AM

KEY WORDS:

Airdrome, Fog, process of formation

PAGES: 64
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUBÁREA: Meteorologia
SUMMARY:

The main objectives of this work are: 1) to study the physical processes of fog formation, 2) to understand the difference between aerodromes and 3) to elaborate an operational forecasting method. Of the total amount of 1554 occurrences recorded by meteorological stations (EMS), in 10 years, 1539 occurrences were in SBEG and 15 in SBMN. The study followed separating the cases according to the rainy, transitional and dry seasons and the years with the highest number of cases. Fourteen cases were selected for a partial analysis, nine in Eduardo Gomes and five in Ponta Pelada. The partial analysis consisted on: (1) Analysis of surface variables (air temperature at 2m (TT), relative humidity (RH), wind direction and speed) and (2) Thermodynamic analysis (Vertical profile of temperature and humidity constructed by reanalysis data and Observed profile). One case was chosen for a complete analysis, which includes a study of the synoptic situation (using different reanalysis products and infrared channel satellite images) and the prediction of low visibility by the PAFOG model. Preliminary results showed that the mean air temperature among the cases was lower in the rainy season, followed by the dry season and the transitional season. Consequently, relative humidity awere lower in the transitional season and higher in the rainy season. This behavior in the surface variables occurred in the same way in Ponta Pelada, except for the wind. Although the velocity was weak (< 3 knots) for all analyzed cases, the predominant direction in SBEG, in all stations, was north-northwest, while in SBMN it was not possible to determine the predominance, due to the observed variations. From the vertical profiles, it was observed that the fog cases (in all stations for both aerodromes) were formed under these conditions: 1) absence of inversion; 2) light conditional instability; 3) weak convection potential. In the study case, the surface variables and the vertical temperature profile showed that, although the two aerodromes had potential for fog formation, the event was formed only in Eduardo Gomes. The predominant wind direction was the differential variable between aerodromes. Satellite images showed low cloudiness or clear sky at the time of the occurred event. Synoptic analysis showed that SBEG and SBMN were under the influence of the interaction between two high-level cyclonic vortices, one of them in the Northern Hemisphere. This interaction caused areas of subsidence and inhibition of cloud formation. PAFOG was considered satisfactory for forecasting low visibility 6h in advance. Local vegetation and wind direction were important factors that influenced the difference between the number of cases at SBEG and SBMN aerodromes. The transport of humidity by the wind from the dense and humid forest around SBEG favored the accumulation of humidity on the surface and the fog formation at the aerodrome. SBMN is surrounded by low vegetation and its main source of humidity is the Rio Negro river located near the aerodrome. This source alone was not sufficient to obtain a frequency of fog events.

BANKING MEMBERS:
Externa à Instituição - ROSA MARIA NASCIMENTO DOS SANTOS - UEA
Interno - 2548280 - HUMBERTO ALVES BARBOSA
Presidente - 1099304 - NATALIA FEDOROVA