In the next few articles and activities, we will explore the build up to and impact of the floods in Pakistan in 2010 in order to consider the relationship between the environment, hazards and those who live there.
Southwestern Asia, India and Bangladesh receive summer monsoonal rain. Nearby Pakistan normally receives less intense, more intermittent summer rains, usually confined to the northeastern regions. Pakistan tends to be characterised by dry weather and even water shortages during the annual cycle.
However, in 2010 rainfall was abnormally high across Pakistan, resulting in widespread flooding through the Indus River catchment. 2010 was a La Niña year, a period when air pressure and ocean circulation shifts, increasing the temperature of surface water in oceans, increasing the moisture in the air and the rainfall. But even for a La Niña period, the rainfall was unprecedented.
Rainfall and flooding commenced in July and continued until September. In areas where the topography was steep, the ground was dry and deforestation had reduced the absorptive capacity of the ground, rivers rose rapidly in upland areas. Gaurav et al. (2011) identified that the flood water volumes were so great that they breached flood assets, river embankments and river-fed canals, or exceeded the design capacity of flood assets at numerous points along the rivers.
Gaurav, K., Sinha, R., and Panda, P. K. (2010) ‘The Indus flood of 2010 in Pakistan: a perspective analysis using remote sensing data’. Natural Hazards 59, 1815