Pakistan is a nation subject to many natural hazards. One of its most vulnerable areas is the coastline. There, people are vulnerable to the dangers that the ocean can bring to land, oceanic flooding. Oceanic flooding is not very common because the sea level typically remains static. But sea level can still change in many ways and there can be other ways for water to get onto land.
Sea level can change due to the tides, ocean temperature, and atmospheric pressure. Low pressure, high temperatures, and certain positions the Earth takes in respect to the Moon and the Sun raise sea level. Then there is the global sea level rise caused by climate change, as the oceans warm and large amounts of ice melt into the ocean. There are also processes that can lift seawater and carry it onto land, namely storm surges and tsunamis. Finally, it rarely happens but there are ways for land to go under the ocean. The boundary between dry land and water is rarely static and this goes for the ocean as well as freshwater bodies, to the extent that sea coasts are among the most dynamic environments on the planet. The purpose of this article is to show just how severe the potential for disaster is from the dynamism of Pakistan’s 650 mile-long coastline with the Arabian Sea.
Most of the coastline consists of the Makran Coast, which comprises the coast of the province of Balochistan. This area has a very rugged and varied topography due to tectonic action. Much of the coast itself consists of flat plains, with mountainous terrain close by inland, but cliffs and hills also rise out of the ocean in many places. The coast of Sindh is generally low-lying. This generally holds true for the westernmost portion, but next to it, the Indus Delta, which is very low-lying throughout, comprises most of the Sindhi coast. This is where the Indus River branches out into several small rivers which run into the ocean. The Indus brings a lot of sediment with it, causing the coastline to change over time. The area hosts many mangrove forests. East of the delta, Pakistan,s coastline consists of the Great Rann of Kutch, a coastal salt marsh in which the tides regularly flood the coast, creating salt-filled sediment inhabited by salt-tolerant plants.