1.5 Weather Hazards and Climate Flashcards
Describe the Greenhouse Effect
use a description and diagram
The Greenhouse Effect is the effect by which short wavelength radiation, emitted by the sun, passes through the atmosphere and is largely absorbed by the Earth’s crust. However, some is reflected back out of the atmosphere. If this radiation, as it reaches the atmosphere, hits any greenhouse gasses, they will absorb this and re-emit it as further long wavelength radiation which can not pass through the atmosphere. Long wavelength radiation is also known as thermal radiation as it causes heat. In this way, greenhouse gasses create a blanket that surrounds the atmosphere keeping warmth trapped inside. (See Figure 1, Page 1 of older)
What is a Greenhouse gas
A gas which re-emits short wavelength radiation as long wavelength radiation. (i.e.: carbon dioxide, water vapour, methane, nitrous oxide, ozone)
Define Enhanced Greenhouse effect
The Enhanced Greenhouse effect is just the Greenhouse Effect enhanced by human activity (i.e.: burning fossil fuels). (See Figure 1, Page 1 of folder)
Define Thermal Expansion
Thermal expansion is the tendency of matter to change its shape, area, and volume in response to a change in temperature.
Define Quaternary Period
The Quaternary Period is a geologic time period that encompasses the most recent 2.6 million years — including the present day.
Define Climate Change
Climate change refers to significant changes in global temperature, precipitation, wind patterns and other measures of climate that occur over several decades or longer.
Define Interglacial Period
The Interglacial period is a period of relatively warmer weather between ice ages.
Define Glacial Period
The Glacial period is a period of relatively cooler weather that causes ice ages.
Define Eccentricity
Eccentricity are the changes to the Earth’s orbit causing greater or lesser differentiation between temperatures during different seasons. At times the orbit is more circular and at others it is more elliptical. (See Figure 2, Page 1 of folder)
Define Axial Tilt
Earth’s axial tilt actually oscillates between 22.1 and 24.5 degrees. The reason for this changing obliquity angle is that Earth’s axis also wobbles around itself. This wobble motion is called axial precession. Depending on how tilted towards the sun the Earth is, there can be more or less heat in certain areas, this occurs every 41, 000 years. (See Figure 3, Page 2 of folder)
Define Inter Tropical Convergence Zone (ITCZ)
The Inter Tropical Convergence Zone, or ITCZ, is a belt of low pressure which circles the Earth near the equator where the trade winds of the Northern and Southern Hemispheres come together.
Define Jet Streams
Jet streams are fast flowing, narrow, meandering air currents in the atmospheres usually where climatic cells meet.
Define Ocean Circulation
Ocean circulation is the large, connected system of water movements in the oceans. It involves both surface and deep currents.
Define Solar Radiation
Solar radiation is the radiant energy emitted by the sun.
Define Trade Winds
Trade winds are a wind blowing steadily towards the equator from the north-east in the northern hemisphere or the south-east in the southern hemisphere, especially at sea. (See Figure 4, Page 2 of folder)
Define Magnitude
Magnitude is the great size or extent of something.
Define Frequency
Frequency is the rate at which something occurs over a particular period of time or in a given sample.
Define Social Impacts
An social impact is the effect of an event on people or the society.
Define Economic Impacts
An economic impact is the effect of an event on money or the economy.
Define Environmental Impacts
An environmental impact is the effect of an event on the natural world.
Define Vulnerability
Vulnerability is the quality or state of being exposed to the possibility of being attacked or harmed, either physically or emotionally.
Define Meteorological Drought
Meteorological drought is when an area has less water than usual over a sustained period of time due to changes in the weather. (i.e: changing wind patterns)
Define Hydrological Drought
Hydrological drought is when an area has less water than usual over a sustained period of time due to changes in water patterns. (i.e.: less snow melting into rivers)
Define Storm Surge
The rising of the sea due to winds/pressure associated with a storm.
Define Global Atmospheric Circulation
Global atmospheric circulation is the large-scale movement of air by which heat is distributed on the surface of the Earth. This occurs around three conventional cells: Hadley cell, the Ferrel cell, and the Polar cell. (See Figure 4, Page 2 of folder)
Define Hadley Cell
The Hadley cells are between 30°N - 60°N and 30°S - 60°S. (See Figure 4, Page 2 of folder)
Define Ferrel Cell
The Ferrel cells are between 0° - 30°N and 0° - 30°S. (See Figure 4, Page 2 of folder)
Define Polar Cell
The Polar cells are between 60°N - 90°N and 60°S - 90°S. (See Figure 4, Page 2 of folder)
Define Natural Hazard
A natural hazard is a natural phenomenon that might have a negative effect on humans or the environment.
Define Saffir-Simpson Scale
The Saffir-Simpson tropical storm wind scale is a 1 to 5 rating based on a tropical storm’s sustained wind speed. This scale estimates potential property damage. The moment a tropical storm hits 1 on the scale it becomes a hurricane. ( For wind speeds See Figure 5, Page 3)
At which point scale does a tropical storm become a hurricane?
At 74mph, a tropical storm becomes a hurricane.
Define Coriolis Effect
The Coriolis effect tends to deflect winds to the right in the northern hemisphere and to the left in the southern and is important in the formation of cyclonic weather systems. This is due to the spinning of the Earth. (See Figure 4, Page 2 of folder)
Define Prevailing Wind
Prevailing wind is a wind from the direction that is predominant or most usual at a particular place or season.
Define Over Abstraction
Over abstraction is when water is taken from aquifers, groundwater levels fall. If the amount of water taken is greater than the amount of water falling as rain, it is called over-abstraction .
Define Ice Cores and Explain their uses
The ice core is the centre of a glacier, depending on the quantity of sheets that surround it, an ice core can tell us the age of ice or what the atmosphere was like at the time the core formed. This can tell us about the early atmosphere.
Define Pollen Records and Explain their uses
Pollen records are pollen analysis from small particles of pollen that become trapped in fossils or rocks. These can help us analyse what the atmosphere was like at the time.
Describe El Niño Effect
The term El Niño refers to the large-scale ocean-atmosphere climate interaction linked to a periodic warming in sea surface temperatures across the central and east-central Equatorial Pacific. This causes a change in weather patterns globally. ( See Figure 6, Page 3 of folder)
Describe La Niña Effect
La Niña is thus defined as the intense cooling of the eastern and central tropical Pacific Ocean, frequently experienced together with warmer than normal sea surface temperatures in the west side of the Pacific. Just like an El Niño event, La Niña is tied to increased chances of extensive changes in global weather.
Define Ocean Currents
An ocean current is any more or less permanent or continuous, directed movement of ocean water that flows in one of the Earth’s oceans.
This is caused by the Earths rotation, wind, temperature, salinity and the moon’s gravity.
Define Tree Rings
Tree Rings are circles that appear around each other in the cross section of tree trunks.
What is the name given to calculating age using Tree Rings?
Dendrochronology
“dendron” - tree
“khronos” - time
“logia” - study of
What are Historical Records?
Historical Records are any evidence written or noted by people in the past, some are more reliable than others.
Give some examples of Historical Records?
Diary Newspaper Book Tapestry Painting Drawing Notes (preferably academic)
Describe the Milankovitch cycle
The Milankovitch cycle is the changes in the Earths’ orbit and rotation. It encompasses axial, eccentricity and precession.
(See Figure 2 and 3, Page 1 and 2 of folder)
Describe Precession
Precession is a change in the orientation of the rotational axis of the Earth. (See Figure 7, Page 4)
Describe Sun Spots and Solar Variation
Sunspots are darker, cooler spots on the sun, when these shine towards the sun they cause solar variation, this means the amount of solar energy is less than usual.
Describe the Effect of Volcanoes on the Earths Climate
When Volcanoes erupt, the debris and smoke fly into the atmosphere creating a cloud in the atmosphere this stops solar radiation being able to get in and thus creates a period of cooler weather.
Describe the Effect of Cosmic Material on the Earths Climate
When cosmic material hits the Earth, it causes clouds of debris in the atmosphere this stops solar radiation being able to get in and thus creates a period of cooler weather.
What is Gulf Stream/ North Atlantic Drift?
A warm ocean current of the northern Atlantic Ocean off eastern North America.
What 5 factors effect the UK climate?
1) Maritime Influence
2) Prevailing Wind
3) North Atlantic Drift
4) Atmospheric Circulation
5) Altitude
How does Maritime Influence effect the UK climate?
Most of the air reaching the UK contains lots of moisture, as we are surrounded by sea, leading to rainfall all year.
How does Prevailing Wind effect the UK climate?
The prevailing wind for the UK comes from the South-West. The air travels long distances over the Atlantic Ocean, bringing moisture, leading to more rainfall.
How does North Atlantic Drift effect the UK climate?
This ocean current brings warm water North, to the UK. In the winter this makes the UK climate milder than would be expected for its latitude.
How does Atmospheric Cirulation effect the UK climate?
The UK is near the ‘boundary’ between the northern Ferrel and Polar cells. This is where air from the south and cooler air from the north meet, causing unsettled weather.
How does Altitude effect the UK climate?
The higher an area is, the cooler and wetter it is.
What happened between 950AC and 1100AC?
Medieval Warm Period
Describe the Medieval Warm Period
A period of higher temperatures meant greater crop yield and a growing population.
What caused the Medieval Warm Period?
Solar Radiation
Explain the uses of tree rings
Trees grow 2 rings yearly, a light one in spring and a stronger one in autumn. These can be used to tell scientists about the humidity and oxygen levels in the atmosphere in the past.
What are the perfect conditions for a tropical storm?
Moist air
27°C sea surface temperature
Describe how a tropical storm forms?
Rising warm air causes thunderstorms. These group together, making a strong flow.
An area of very low pressure forms at the centre of the converged storms.
The storms rotate, accelerating in and up, forming a tropical cyclone.
Describe the Coriolis Effect
As the Earth spins, the coriolis effect makes air and water spin
In which direction is the Coriolis effect in the Northern Hemisphere?
Deflects movement to the right
In which direction is the Coriolis effect in the Southern Hemisphere?
Deflects movement to the left
Describe characteristics of a tropical cyclone?
Very Low Pressure
Form a rising, spiralling air surrounding the eye
Cloud banks called the eye wall surround the eye
Often 400km wide and 10km high
Describe the characteristics of the eye
Descending, high pressure air
What speed do cyclones travel at?
Up to 40km/h and 600km/day
Where are cyclones most likely to happen from June to November?
Northern Tropics
Where are cyclones most likely to happen from November to April?
Southern Tropics
What are some natural hazards from a hurricane or cyclone?
Storm Surges Landslides High Winds Intense Rainfall Coastal Flooding
What happens when a cyclone causes a storm surge?
They can cause large masses of water to hit land, causing damage to beaches and coastal habitats.
What happens when a cyclone causes a landslide?
Intense rainfall causes soil to be saturates causing slides
What happens when a cyclone causes coastal flooding?
They can cause large masses of water to hit land. Damage to property and lives is increased due to flooding.
What happens when a cyclone causes intense rainfall?
Heavy or persistent rainfall can lead to flooding, damaging property and leaving people stranded.
What happens when a cyclone causes high winds?
Winds as high as 240km/h can uproot trees and buildings, potentially causing injuries and loss of life.
What is the Saffir Simpson scale?
A scale that categorises cyclones into 5 categories
What does the Saffir Simpson scale categorise based on?
Wind speed and height of storm surge
Name a Hurricane that effected a developed country
Hurricane Sandy
Name a Hurricane that effected a developing country
Typhoon Haiyan
Describe the route of Hurricane Sandy
Travelled across the Caribbean sea, affecting Jamaica, Cuba, Haiti and the USA
When was Hurricane Sandy
22-29 October 2012
What is the maximum speed hurricane Sandy reached?
129km/h
What was the minimum direct death toll of Hurricane Sandy?
At least 150 people
What were the social impacts of Hurricane Sandy in the USA?
At least 150 deaths
Many areas left without electricity
Homes and businesses damaged
Schools closed for days
What were the economic impacts of Hurricane Sandy in the USA?
Estimated property damage $65 billion USD
Petrol had to be bought by the government as supplies ran out
Income from tourism affected by cancellation of New York Marathon
What were the environmental impacts of Hurricane Sandy in the USA?
Storm surges caused significant damage to nature reserves
Raw sewage leaked into waters around NY and New Jersey damaging habitats
Describe the path of Typhoon Haiyan
Formed over the South Pacific Ocean, crossed the Philippines then across to Vietnam, Laos and China
When was typhoon haiyan?
2 November 2013
What speeds did the typhoon reach?
300km/h
What were the social impacts of Typhoon Haiyan in the Philippines?
Estimated 6000 people killed, many still missing
Significant loss of power
Estimated 600 000 displaced from their homes
Homes destroyed
What were the economic impacts of Typhoon Haiyan in the Philippines?
$2 billion USD estimated damages
Damage to infrastructure, blocked transport making aid difficult
What were the environmental impacts of Typhoon Haiyan in the Philippines?
Mangroves damaged
Trees uprooted
Oil spills from a tanker caused sea pollution
Define Drought
A prolonged period of abnormally low rainfall
Describe an arid environment?
Permanent low precipitation
10-250 mm precipitation per year
High pressure, no cloud cover
Mostly located between 23.5°N and 23.5°S
Describe drought conditions?
Temporary low precipitation
High pressure, no cloud cover
Located anywhere globally
In the UK, when is a drought announced?
After 15 consecutive days without rainfall
What are the two types of causes for a drought?
Meteorological
Hydrological
Define meteorological causes of a drought
This is when an area receives less than average precipitation (dry weather)
Define hydrological causes of a drought
This is where the hydrological cycle receives less rainfall than normal leading to low groundwater and unfilled reservoirs (low water supply)
In which cells are there ‘dry’ and ‘wet’ seasons?
Hadley and Ferrel Cell
Name a drought in a developed country
California 2012-2015
Name a drought in a developing country
Ethiopia 1984-2015
What were the three main hazards of the drought in California?
Subsidence
Contamination
Wildfires
Describe Subsidence
Land sinks or gradually caves in as groundwater levels drop, causing land to settle at a lower level
How is water contaminated during droughts? (Specifically in Califronia)
Land and Drinking water may be contaminated by seawater, drawn inland by a lack of pressure
Why was the risk of wildfires higher during the California drought?
The dry vegetation allows fires to spread quickly
What was the worst affected area of Califronia by drought in 2015?
Central Valley
What were the environmental impacts of the California drought?
Wetlands and rivers got less water as water was diverted
Wildfires caused air pollution and damaged wildlife
What were the social impacts of the California drought?
Wildfires provided risk to people’s lives and properties
Infrastructure damage
Less state money to spend on services for people
Crop damage meant loss of food and income
What were the economic impacts of the California drought?
Cost Californian state $2.7 billion USD per year
542000 acres taken out of crop production
Infrastructure damage
How long did the drought last in Ethiopia?
About 30 years
What caused drought in Ethiopia?
The rainy period getting shorter (hydrological)
Why was the drought so impacting on the economy in Ethiopia?
85% of the population relied on subsidence farming
Define Subsidence Farming
Farming enough to maintain you self and you family but not enough to provide a steady income
What were the social impacts of the Ethiopian drought?
Food crisis due to death of livestock and loss of crops
People eating less caused malnutrition
Less girls went to school as they had to spend their day getting water
Long grass used for roofing didn’t grow meaning homes were unprotected
What were the economic impacts of the Ethiopian drought?
200 000 hectares lost to fire
Loss of crops and livestock
Price of maize increased
What were the environmental impacts of the Ethiopian drought?
Loss of habitats for fish and wildlife Disease among wild animals Migration 200 000 hectares lost to fire Extinction Wind and water erosion of soil
What did the Californian government do in response to the drought?
Public education water campaigns
25% cut in water use (hose ban)
What did the Californian organisations do in response to the drought?
Investigations into effective groundwater managing
What did the Californian individuals do in response to the drought?
Farmers encourages to use water-efficient irrigation
Homeowners encouraged to check for leaks
Protestors campaigned against local bottles water companies
What did individuals do in response to the Ethiopian droughts?
Large charity events (Live Aid) have helped raise awareness and money
What did oversea governments do in response to the Ethiopian droughts?
The USA gave $128.4 million USD in food aid to Ethiopia in 2015
What did organisations do in response to the Ethiopian droughts?
Aid agencies such as Oxfam and UNICEF helped people get supplies
Education charities are helping urbanisation
What were the main hazards of the Ethiopian drought?
Reduction in crop yield
Longer journeys to find water
Migration
