heat waves and droughts


Droughts also depend on what is normal for a region. When a region gets significantly less precipitation than normal for an extended period of time, it is in drought. The Southern United States is experiencing an ongoing and prolonged drought. Drought has many consequences. When soil loses moisture it may blow away, as happened during the Dust Bowl in the United States in the 1930s. Forests may be lost, dust storms may become common, and wildlife are disturbed. Wildfires become much more common during times of drought.

heat waves

A heat wave is different depending on its location. According to the World Meteorological Organization, a region is in a heat wave if it has more than five consecutive days of temperatures that are more than 9 F (5 C) above average. Heat waves have increased in frequency and duration in recent years. The summer 2011 North American heat wave brought record temperatures across the Midwestern and Eastern United States. Many states and localities broke records for temperatures and for most days above 100 F.


A high pressure cell sitting over a region with no movement is the likely cause of a heat wave. What do you think caused the heat wave in the image below (Figure 1.1)? A high pressure zone kept the jet stream further north than normal for August. A heat wave over the United States as in- dicated by heat radiated from the ground. The bright yellow areas are the hottest and the blue and white are coolest. Click image to the left or use the URL below. URL: Click image to the left or use the URL below. URL:


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what causes a heat wave?

a) a high pressure cell sits over a region.

b) a high pressure zone keeps the jet stream from moving south as it normally does.

c) solar radiation increases due to solar storms.

-->  d) a & b

heat waves have increased in frequency and duration in recent years.

-->  a) true

b) false

a region is having a heat wave when it is experiencing more than _ consecutive days of temperatures more than ___ above the average.

a) 3; 3of (1.7oc)

-->  b) 5; 9of (5oc)

c) 10; 12of (6.7o

d) 7; 15of (8.3oc)

wildfires are increasingly common in the western united states due to an extended

-->  a) drought

b) heat wave

c) monsoon season

d) a & b

three months with average daily high temperatures above 100of is normal for phoenix, arizona, but six days of 100of temperatures in portland, oregon is a heat wave.

-->  a) true

b) false

droughts in the 1930s were a major factor in causing this event.

a) the great depression

b) world war ii

-->  c) the dust bowl

d) the green revolution

people survive in phoenix, arizona in intense heat because they are hardier than people in other locations.

a) true

-->  b) false

what are some consequences of droughts?

a) soil loss

b) trees in forests die.

c) ecosystems damaged.

-->  d) all of these.

more people die in heat waves than in blizzards, tornadoes or hurricanes.

-->  a) true

b) false

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