Geofizika, Vol. 26 No. 1, 2009.
Izvorni znanstveni članak
Mesoscale equatorial wind prediction in Southeast Asia during a haze episode of 2005
Mahmud Mastura
; Earth Observation Centre, Faculty of Social Sciences and Humanities, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
Sažetak
Even today fires are still utilized by local farmers in Southeast Asia to clear land. Air pollutants produced from the biomass burning activities from Sumatera, for example, are advected towards the western coast of Peninsular Malaysia during the southwest monsoon and can cause adverse effects on the health of the local population. This study utilized the TAPM (The Air Pollution Model) to predict the low level mesoscale characteristics in an equatorial environment that encompassed the island of Sumatera and Peninsular Malaysia during the burning period in August 2005, when persistent haze was prevalent.
TAPM was able to generate the existence of the daily land and sea breeze conditions near the western coast of the Peninsular Malaysia with relative success with a moderately high Index of Agreement of 0.87 and 0.60 for the zonal and meridional wind components, respectively, even without assimilation of local wind conditions. Strong low level southwesterlies that were generated during the daytime over the Straits of Malacca were associated with sea breeze, while weak southeasterlies simulated from 1900 local time towards midnight were associated with land breeze conditions. The vertical wind profile within the lowest kilometer of the atmosphere showed that the weak southwesterlies were present from mid-morning to sunset, which was interspersed with stronger southwesterlies that generally occurred above the height of 400 m. The meteorological parameters such as wind speed, temperature, and humidity were successfully simulated by the model with comparatively high correlation coefficients, low RMSEs and high indices of agreement with observed values.
The vertical turbulent kinetic energy profiles showed presence of low level suppression at a height below 600 m during the height of the haze in August 2005, which coincided with the intense burning activities in Sumatera and the elevated levels of pollution in western Peninsular Malaysia. Trajectory analysis showed that aged air articles were advected landwards and seawards throughout the duration of the seven days’ simulation from the 7th to the 13th of August 2005. The presence of recirculation features of the land and sea breeze conditions highlighted the poor transportation capability of low level winds that were unable to cope with the high loadings of aerosols from the biomass burning in Sumatera.
Ključne riječi
equatorial region; meteorological parameters; biomass burning; transportation of haze; Southeast Asia
Hrčak ID:
40226
URI
Datum izdavanja:
30.6.2009.
Posjeta: 1.500 *