Sea-Breeze Front Propagation over The Northern Coast of West Java and Association with Inland Convections in The Dry Season Banu W. Yonas (a*,b), Tri W. Hadi (a)
a) Faculty of Earth Science and Technology, Bandung Institute of Technology
b) Meteorology, Climatology, and Geophysical Agency, Indonesia
Jalan Ganesha 10, Bandung 40132, Indonesia
*banuyonas[at]gmail.com
Abstract
Sea-breeze circulation is known to well develop during the dry season months of July to September over the northern coast of West Java. On the other hand, compared to other areas in Java Island, strong convection and heavy rainfall more frequently occur in the most western part of the Island during the dry season. This study investigates the relationships between sea-breeze development and propagation, and the convections around this region. By analyzing surface winds and relative humidity observed over two sites near Jakarta, sea-breeze intrusion times and the speed of sea-breeze front propagation can be estimated. It is found that on average, sea-breeze develops around 09:00 LT and propagates at a speed of about 1.44 m/s near over the coastal plain. However, there is also variation in the sea-breeze propagation speed ranging from 0.49 m/s to 4.69 m/s. Meanwhile, convective activites are identified from satellite imageries. Further analyses reveal that faster sea-breeze propagation tend to be associated with deeper and larger convections, compared to the slower ones. This indicates that sea-breeze propagates faster under more unstable atmosphere, consistent with previous studies. Impacts of collisions of sea-breezes developed over different coastlines have not been thoroughly analyzed in this study.
