Natural Hazards: Causes and Effects - Disaster Management Center ...

1. Environmental Effects
Tropical Cyclone Disaster Overview
Effects Consequences
High Winds Damage structures; destroy some standing crops; damage orchards and trees
Intense Rains Cause flooding that damages structures, may cause evacuations, landslides;
damage certain crops (tubers); erosion
Storm surge Causes rapid flooding with above effects; scours and erodes topsoil; may
increase salinity in subsurface water; destroys most crops
2. Patterns of Injury and Surgical Needs in Disasters
Without storm surges, injuries exceed deaths. Moderate surgical needs.
With storm surges, deaths exceed injuries. Moderate surgical needs within first 72 hours.
3. Patterns of Disease Resulting from Disasters
Actual Immediate Epidemiological Threat Secondary Epidemiological Threat
None Waterborne diseases (except cholera), vectorborne diseases
4. Immediate Social and Economic Consequences of Disasters
Loss of housing Disruption of marketing systems
Loss of industrial production Disruption of communications
Loss of business production Looting
Damage to infrastructure
5. Effects of Natural Hazards
On Land Structures Agriculture Trees
High Winds Damages buildings, Damage to standing Widespread
power lines, towers crops such as grains loss of timber
Flooding Damages structures Damage to standing crops Minor losses
in flood areas
Flooding Extensive damage to Extensive damage to crops, Loss of trees
(storm surge) structures, roads, etc. irrigation systems; leaves
harmful salt deposits, scours
topsoil, contaminates wells
6. Response to Disasters (Ideal)
Initial Response:
By Local Authorities By Foreign Intervenors
Evacuation; search and rescue; medical assistance; Cash; assistance in reopening roads,
disaster assessment; provision of short-term food/water; re-establishing communications, contact
water purification; epid. surveillance; with remote areas; disaster assessment;
provision of temporary lodging. assistance with water purification.
Secondary Response:
Repair/reconstruction of infrastructure, housing, Repair/reconstruction of housing; jobs;
public buildings; jobs; assistance to agriculture, credit; technical assistance to
small business, fishermen. agriculture, small business, institutions.
7. Appropriate Aid
cash loans or credit blankets
temporary lodging agricultural assistace short-term feeding (normal foods)