EQ3 2B.9

Question 1

What local factors affect flood risks

Answer 1

Height - low lying makes more susceptible to storm surges and SLR

Subsidence - low lying coastlines in estuaries or deltas experience this bc of sediment settling and compacting

Vegetation removal - salt marshes, mangroves reduce flood risk as it stabilises sediment and absorbs wave energy

Question 2

What is a depression

Answer 2

Area of low air pressure generating surface winds that spiral into the centre of low pressure in an anti-clockwise direction

Question 3

Where do depressions occur

Answer 3

Mid-latitudes

Question 4

What are storms

Answer 4

Depression areas of low surface pressure that generate strong winds

Occur just north and south of the equator

C\lassified on the Saffir Simpson scale into 5 categories, where the fifth has winds of over 250 km.

Question 5

How do storms affect sea levels

Answer 5

Cause storm surge - temporary rise in local sea level produced when a depression, storm or tropical cyclone, reaches the coast

High air pressure depresses the ocean surface, lowering local sea level, low air pressure allows ocean surface to dome upwards, raising local sea level

Question 6

Short term impacts of storm surges

Answer 6

Deaths and injuries - thru drowning/collapsing buildings, hypothermia/water born diseases

Destruction of infrastructure

Damaged water pipes

Homes destroyed

Businesses destroyed

Question 7

Are the IPCC sure on SLR

Answer 7

Sea level will rise by 18-59 cm by 2100
-pace and extent is uncertain due to population growth, economic development, natural positive and negative feedback, political commitment to restrict GHG emissions
-affected by adaption and mitigation

Question 8

Are the IPCC sure on delta flooding

Answer 8

Area of the world’s major deltas at risk from coastal flooding is likely to increase by 50%

Question 9

Are the IPCC sure on wind and waves or coastal erosion

Answer 9

Somewhat

Wind and waves - some evidence of increase wind speeds and large waves
Coastal erosion - erosion generally increase due to combined effects of changes to weather systems and sea level

Question 10

Are the IPCC sure on tropical cyclones, storm surges and depressions

Answer 10

Uncertain

Tropical cyclone frequency is likely to remain unchanged, but could be more larger storms due to warmer ocean surface temp

Storm surges linked to depressions, likely to become more common, maybe more intense

Depressions - polar front jet streams will accelerate, possibly increasing number and intensity of depressions and storm surges in mid-latitudes