A case study of flooding in a rich part of the world and one from a poorer area-the different effects of and responses to flooding. England (MEDC) Bangladesh (LEDC) Date & July 2007 Summer 2004 Time Changes in the JET STREAM THREE MAJOR RIVERS The unusual position of the Atlantic jet stream The Meghna, Brahmaputra and Ganges rivers has been blamed by some. "This year it has been flow through Bangladesh from India and the much FURTHER SOUTH for much of the summer Himalayas to their mouth at the Bay of Bengal, resulting in areas of LOW PRESSURE (a bringing water into Bangladesh from a catchment depression) right across the UK which causes 12 times the size of Bangladesh itself. HEAVY RAIN," Convergence of Air Masses Heavy Rainfall and a MONSOON CLIMATE, heavy rains between May- September every year, when moist winds blow from the sea. The continuous rainfall fell on saturated soil increasing surface runoff into rivers Melting snow From glaciers in the Himalayan mountains during On Friday July 21st, a cool weather system late spring and summer increased discharge in spinning over the Atlantic drifted into Britain and the Brahmaputa and Ganges river. collided with warm air that was bringing heat Peak discharge occurred in both rivers at the waves to Spain, France and eastern Europe. The same time which increased discharge down Physical warm air rose, cooled, contracted and released its stream - moisture in a 24-hour of non-stop rain. TROPICAL CYCLONES cause storm surges where Heavy Rainfall sea water is funnelled up the Bay of Bengal and As a result, during May June and July the onto low lying coastal areas causing coastal rainfall in the Severn Valley was higher than CAUSE flooding. Coastal flooding also hinders the usual 400mm fell across the UK. It was the drainage of the 3 major rivers, into the sea wettest period since records began in 1776 causing the water to back up making them more water soaked into the ground it became prone to flooding. saturated. Almost two months of rain fell in one day on Relief LOW, FLAT COUNTRY. 80% of Bangladesh Friday 21st July 2007. is located on floodplains and river deltas, 70% is less than 1 metre above sea level, so once the rivers overflow the water can spread vast RELIEF The flat and low-lying nature of the distances. landscape surrounding the river Severn. When water breached the banks of the River Severn’s channel it just spread across the land for long distances
A case study of flooding in a rich part of the world and one from a poorer area-the different effects of and responses to flooding. England (MEDC) Bangladesh (LEDC) Date & Time July 2007 Summer 2004 CAUSE - Physical Changes in the JET STREAM The unusual position of the Atlantic jet stream has been blamed by some. "This year it has been much FURTHER SOUTH for much of the summer resulting in areas of LOW PRESSURE (a depression) right across the UK which causes HEAVY RAIN," Convergence of Air Masses On Friday July 21st, a cool weather system spinning over the Atlantic drifted into Britain and collided with warm air that was bringing heat waves to Spain, France and eastern Europe. The warm air rose, cooled, contracted and released its moisture in a 24-hour of non-stop rain. Heavy Rainfall As a result, during May June and July the rainfall in the Severn Valley was higher than usual 400mm fell across the UK. It was the wettest period since records began in 1776 water soaked into the ground it became saturated. Almost two months of rain fell in one day on Friday 21st July 2007. RELIEF The flat and low-lying nature of the landscape surrounding the river Severn. When water breached the banks of the River Severn’s channel it just spread across the land for long distances THREE MAJOR RIVERS The Meghna, Brahmaputra and Ganges rivers flow through Bangladesh from India and the Himalayas to their mouth at the Bay of Bengal, bringing water into Bangladesh from a catchment 12 times the size of Bangladesh itself. Heavy Rainfall and a MONSOON CLIMATE, heavy rains between May- September every year, when moist winds blow from the sea. The continuous rainfall fell on saturated soil increasing surface runoff into rivers Melting snow From glaciers in the Himalayan mountains during late spring and summer increased discharge in the Brahmaputa and Ganges river. Peak discharge occurred in both rivers at the same time which increased discharge down stream TROPICAL CYCLONES cause storm surges where sea water is funnelled up the Bay of Bengal and onto low lying coastal areas causing coastal flooding. Coastal flooding also hinders the drainage of the 3 major rivers, into the sea causing the water to back up making them more prone to flooding. Relief LOW, FLAT COUNTRY. 80% of Bangladesh is located on floodplains and river deltas, 70% is less than 1 metre above sea level, so once the rivers overflow the water can spread vast distances.
Water%20on%20the%20land%20%20Case%20Study%20RCL.docx