Drought and desertification

Question 1

what is a drought

Answer 1

“a drought is an extended period of dryness; usually any period of moisture deficiency, that is below normal for a specific area”.

Question 2

what is a Meteorological drought

Answer 2

is when the precipitation is less than normal

Question 3

what is Agricultural drought

Answer 3

is when the moisture in the soil no longer meets the needs of a specific crop.

Question 4

what is Hydrological drought

Answer 4

when surface and subsurface water levels are below normal.

Question 5

what is Socio-economic drought

Answer 5

when water scarcity starts to affect people.

Question 6

what is The Palmer Drought Severity Index

Answer 6

Measures how far a region is below normal precipitation, using the variables of precipitation including snowfall, surface air temperature, soil moisture, evapotranspiration, and runoff.

Question 7

what do negative and positive numbers show on the PDSI

Answer 7

Negative PDSI numbers indicate drought and positive numbers indicate moisture.

Question 8

what are the four classifications of droughts using the PDSI

Answer 8

• Mild drought -1 to - 1.99 PDSI
• Moderate drought -2** to -2.99 PDSI
• Severe drought -3** to -3.99 PDSI
• Extreme drought- -4 PDSI or less

Question 9

2 good things about the palmer drought severity index

Answer 9

The PDSI is the first comprehensive drought index and it is also standardised

Question 10

3 pros of the Plamer drought severity index

Answer 10

• First comprehensive drought index
• A ‘standardized’ drought index,
• Effective in determining long‐term drought, especially over low and middle latitudes.

Question 11

why is it good that the drought severity index is standardised

Answer 11

makes easier comparison at different locations/times

Question 12

what are the two cons of the drought severity index?

Answer 12

• it may lag emerging droughts by several months

- doesn’t account for delayed runoff from snow/ice.

Question 13

what is the global drought monitor

Answer 13

The global drought monitor takes into account various measures of droughts to calculate the return interval for various severities of droughts.

Question 14

what are 6 economic impacts of droughts

Answer 14

droughts can lead to loss of livestock production
loss of crop production
increased energy demand
loss of tourism
income loss for farmers
decreased land prices etc.

Question 15

3 environmental impacts of droughts

Answer 15

droughts damage animal species, plant species, wetlands.
impact air quality due to dust.
Increased stress on endangered species or even extinction

Question 16

3 social impacts from droughts

Answer 16

food shortages
mental and physical stress
migration,
increased conflict,

Question 17

where had the biggest drought, what country, what year how many people died

Answer 17

China has the greatest number of drought fatalities, with 3 million people dying in 1928.

Question 18

how many people died in sudan, what year.

Answer 18

Recently, 150,000 people died in Sudan in 1985.

Question 19

years that are generally warmer have what

Answer 19

Years with higher temperatures generally have higher overall mortality rates.

Question 20

what is the response to droughts in the global south, what is good about it what is bad about it?

Answer 20

there is often a call for international aid, partly in the form of food rations. This is crucial during times of famine but can flood local markets and put farmers out of business.

Question 21

what response is common to droughts in the global north

Answer 21

governments put water-saving measures into place such as hosepipe bans.

Question 22

what are some of the effects of droughts in the global north,

Answer 22

Droughts can cause ground subsistence which can damage building foundations and cause railways to buckle.

Question 23

what is desertification

Answer 23

the degradation of a semi-arid region caused by natural or human factors resulting in more extreme arid conditions.

Question 24

what is normally associated with droughts

Answer 24

It’s often associated with droughts as droughts can accelerate the degradation of non-desert land so that it becomes a desert.

Question 25

3 Classifications of arid lands

Answer 25

• Semi-arid/steppe - 250-500mm rain per year
• Arid/desert- 25- 250 mm rain per year
• Hyper arid/desert- under 25mm rain a year, or over 12 months with no precipitation.

Question 26

explain the distribution of non-polar arid landscapes in the world

Answer 26

Non-polar arid land is typically distributed across the Andes, the Sahara, the Middle East, and Central Asia, Southern Africa, Australia, and the West Coast American deserts.

Question 27

in regards to the distribution of nonpolar arid land, where in the world is it most populated

Answer 27

Of these areas, the most densely populated is central/southern Asia.

Question 28

what are 4 impacts of desertification?

Answer 28

• poor land use including overgrazing and improper cultivation
• soil depletion
• poor irrigation practices
• deforestation.

Question 29

what is the American dust bowl, and what caused it when

Answer 29

There was extensive dust storm damage from 1933-1939

Question 30

what did the government do when the American dust bowl settle

Answer 30

the government had sold semi-arid land to farmers when they settled

Question 31

on average how much rain does the north and south sehal get?

Answer 31

drought north gets less than 300ml and the south gets less than 900ml.

Question 32

where is the Sahal?

Answer 32

the Sahel includes Mauritania, Mali, Niger, Chad, Sudan, Ethiopia, and Somalia.

Question 33

a serious drought took many lives in the sahal, when was it and how many lives were lost, why did they die?

Answer 33

Between 1972-1975, over 600,000 died as a result of starvation, gastroenteritis, etc.

Question 34

what are 4 reasons the droughts affect the sahal so extremely

Answer 34

• a population boom in the past 70 years
• mostly pastoral economies where goats are a sign of wealth, international development paid for many new water wells which resulted in herd expansions.
• Political and ethnic tensions,
• climate change.