Thursday, October 28, 2010
Last blogged @ 11:42 AM

Droughts

Drought is a period or condition of unusually dry weather within a geographic area where rainfall is normally present. During a drought there is a lack of precipitation. Droughts occur in all climatic zones. However, its characteristics vary significantly from one region to another.

4 main kinds of droughts:

 Agricultural Drought

• Effects mainly food production and farming.
• Precipitation shortages bring soil water deficits, reduced ground water or reservoir levels, and etc.
• Deficient topsoil moisture at planting may stop germination thus leading to low plant populations.

 Hydrological Drought

• Associated with effects of periods of precipitation shortages on water supply.
• Water in hydrologic storage systems such as reservoirs and rivers are often used for multiple purposes i.e : Flood Control, Irrigation, Recreation, Navigation, Hydropower, Wildlife Habitat.
• Competition for water in these storage systems escalates during drought →conflicts between water users increase significantly.

 Meteorological Drought

• Is the amount of dryness and the duration of the dry period.
• Atmospheric conditions that result in deficiencies of precipitation change from area to area.

Socioeconomic Drought

• Occurs when the demand for an economic good exceeds supply due to weather-related shortfall in water supply.
• Supply of many economic goods, such as water, forage, food grains, fish and hydroelectric power, depends on weather.
• Water supply is sufficient in some years but not satisfactory to meet human and environmental needs in other years due to variability of climate.
• Demand for economic goods is increasing as a result of increasing population.
• Supply may also increase due to improved production efficiency and technology.

Effects on Droughts

Economic 
- Loss of national economic growth,thus slowing down of economic development
- Damage to crop quality(Insect infestation and plant disease) → less food production
- Increase in food prices and importation of food → higher costs
- Unemployment from production declines
- Loss to recreational and tourism industry
- Loss of hydroelectric power,navigability of rivers and canals
- Unavailability of water and feed for livestock → high livestock mortality rates → less livestock production → income loss for farmers

Environmental
- Soil Erosion
- Increased desertification
- Damage to plant and animal species
- Reduction and degradation of fish and wildlife habitat
- Lack of feed and drinking water
- Diseases
- Increased predation
- Loss of wildlife in some areas and too many in others
- Increased stress to endangered species
- Increased number and severity of fires


Social
- Loss of human life from food shortages, heat, suicides, violence
- Mental and physical stress
- Conflicts(water user and political)
- Inequity in the distribution of drought relief
- Loss of cultural sites
- Reduced quality of life results in changing of lifestyle
- Increased poverty
- Population migrations
- Social unrest i.e. public dissatisfaction with government regarding drought response

Last blogged @ 10:54 AM

1938 Changsha Fire/Wenxi Fire

http://upload.wikimedia.org/wikipedia

• Greatest human caused city-wide fire that ever besieged China
• Happened in 1938 during the second Sino-Japanese War
• Result in Changsa being one of the most damaged cities during World War II
• Chinese and Japanese armies faced off along the Xinqiang River just outside of Changsha
• Due to lack of confidence of withholding the city, Chiang Kai-Shek decided to burn the entire city
• Reasoned that with the city burned to the ground, Japan would gain nothing even if it chose to forcefully enter it
• Immediately organized an arson team and was ordered to set fire once a signal fire was set off on the top of Tianxin Building in the Southwest of Changsa

At around 2 o'clock in the morning of November 13, 1938, there was a fire in a military hospital just outside of the South Gate (to this day, it remains a mystery whether the fire was a signal or an accident). The arson team took it as a signal and started to set the fire. The burning lasted for five days. At the end of it, historical antiques more than 2500 years old suddenly became ashes. City residents tried their best to escape, resulting in a severe boat accident at a river ford on the Xiang River.

DAMAGE DONE :

• More than 3000 people lost their lives during the fire
• Over 90% or 56 000 of the buildings were burned
• Cost a total economic loss of 1 billion dollars, which account to 43% of the total output of the city
• Government institutions were destroyed
• More than 31 schools including the University of Human were also burned down
• Except for the Xiangya Hospital, every hospital in Changsha was burned to ground 

The fire, however, annihilated all the cultural accumulations that the city retains since the Spring And Autumn period. Ground historical treasures were completely wiped out, causing an immeasurable damage to archaeological studies.

 

Wednesday, October 27, 2010
Last blogged @ 9:33 AM

Molasses Disaster .

Molasses disaster? Can molasses kill people?

Yes, a molasses tank in Boston exploded with great force and flooded the streets with a huge wave of molasses. It killed 21 people, crumpled the steel support of an elevated train, and knocked over a fire station.

 

The Violence of the Explosion

Fermentation, a sudden rise in temperature, and an inadequate tank caused the tank containing two million gallons of molasses to explode. The force of the explosion was so great that:

• Half-inch steel plates of the huge molasses tank were torn apart. ("Seeking Cause of Explosion," The Salem Evening News, January 16, 1919: 7.)
• The plates were propelled in all directions, hard enough to cut the girders of the elevated railway. (Ibid.)
• After the explosion, a tremendous vacuum sucked into ruin buildings which had withstood the primary blast. (Ibid.)
• The vacuum also picked up a truck and dragged it across the street toward the molasses tank. ("Big Molasses Tank Blast Kills Eleven," The Boston Globe, January 16, 1919: 8.)
• An elevated train was lifted off the rails and fell onto the ties. (Ibid.)
• Some buildings collapsed.
• Some buildings were knocked off their foundations.
• Some buildings were buried under the flood of molasses.