Stormy weather Flashcards
Define Hazard risk
The degree of level of harm that will be caused by a natural hazard
Define natural hazard
A natural event that has the potential to cause harm
Economic impact
an impact which affects wealth of a place or sometimes income
Environmental impact
An impact that affects the natural world
Extreme weather
A weather event that is significantly different from the average weather pattern
What is the enhanced green house effect
the stronger impact caused by human emissions of green house gases
What is mitigation
A process which tries to reduce and prevent the effects of something from happening
What is adaption
The process of changing something that can become better suited to its use/ surrounding environment
Define weather
The state of the atmosphere at a particular place or time, including temperature, precipitation, humidity and wind speed
Define climate
the weather conditions prevailing in an area in general or over a long period
define insolation
the amount of solar radiation reaching a given area
define latitude
the angular distance of a place north or south of the earth’s equator, usually expressed in degrees or minutes
what factors affect a places climate
Land relief e.g above sea level, latitude, altitude
Distance from the sea
Distance from the equator
Aridity e.g lack of air moisture
Prevailing wind
Season
Why is the Earth’s atmosphere in constant motion
It is driven by the energy we receive from the sun. We get more energy in tropical areas near the equator and less at the poles. Air movements or winds help to balance this out
How does insolation vary considerably
Places at low latitude have higher levels of insolation as rays are spread over a smaller area (more concentration)
Places at higher latitude e.g poles have lower levels of insolation as the rays are spread over a greater distance/larger area
What is atmospheric pressure
the force by the weight of air above us
Explain convection currents
Warm air rises because it is less dense creating low pressure
Cool air sinks as it is more dense creating high pressure
What causes wind
air particles move from areas of high to areas of low pressure
Describe the global atmospheric circulation model
- air cools and sinks, creating a belt of high pressure and a cold, dry climate
- At about 60 degrees north and south cold polar air mixes with warmer air and rises, creating a blet of low pressure
- Cool air sinks creating a belt of high pressure, as it sinks it becomes warmer and dryer
- warmer air rises, it then cools. Clouds form then and release precipitation
- Above the air will eventually separate and move to higher latitudes
What is low pressure air
Rising air
Creates cold, wet climates
What is high pressure air
Sinking air
Creates warm, dry climates
Why does the equator receive higher levels of insolation
the solar energy strikes the ground at 90 degrees, so energy is concentrates on a small foot print causing eat metre squared to be heated strongly
Describe the Hadley cell
Taking the Hadley cell, warm air at the equator (0° of latitude) rises and then cools in the upper atmosphere, then circles back down towards the tropics (i.e. 30° of latitude).
Describe the ferrel cell
The air in the Ferrell cell moves in the opposite direction to the air in the Hadley cell with warm air moving toward the polar regions. The warm air that has travelled up from the equator converges with the cold air at 60° of latitude that has travelled down from the polar regions. As the air converges the warm air is forced to rise and move back towards the equator.
Describe the polar cell
The overall effect of the Polar cell is to move cold air towards the equator. At the poles (i.e. 90° of latitude) the cold air sinks. It then moves towards the equator. At 60° the combination of warm and cold air causes the warm air to rise, resulting in low air pressure at 60°. At 60° latitude the polar front is found. This is the result of the warm air that has travelled up from the equator and cold air from the poles being unable to mix well.
Describe how the cells are controlled
The Hadley and polar cell are controlled by the sun’s heat whilst the Ferrell cell is controlled by the movement of air in the other two cells
Describe precipitation at the Equator
The intense heating of the Earth’s surface near the equator causes warm, moist air to rise rapidly. As the air rises, it cools and condenses, forming clouds and eventually leading to precipitation. Rainfall is constant throughout the year at the equator
Describe precipitation at the intertropical convergence zone
Near the equator, the trade winds from the northern and southern hemispheres converge. This convergence zone is characterized by rising air, which promotes cloud formation and rainfall, even torrential rain.
Describe precipitation in western Europe
Western Europe typically experiences moderate rainfall throughout the year. However, the distribution and intensity of rainfall vary from region to region. Coastal areas tend to receive more precipitation due to the influence of maritime air masses. In addition jet streams/prevailing winds from the Atlantic bring air full of moisture causing prolonged periods of rain
Describe precipitation in the tropics of cancer and Capricorn
Rain fall is often low but dry air often descends there as part of the Hadley cell resulting in arid conditions
Describe the precipitation at the polar regions
Experience low precipitation due to cold air’s limited capacity to hold moisture. Mostly snow caused by warm-cold air condensing in freezing conditions
Define trade winds
Trade winds are consistent east-to-west prevailing winds found between approximately 30 degrees latitude north and south of the equator. They are driven by the temperature difference between the equator and poles and the Coriolis effect.
Define arid conditions
Arid environments normally have very low rainfall, such as deserts - dry
Define prevailing winds
Prevailing winds are the dominant winds that consistently blow from a particular direction over a specific area. These winds are determined by global atmospheric circulation patterns
So what causes global circulation of wind
Heating at the equator and cooling at the poles
What would happen without wind transporting heat energy
The equator would continually get hotter and the poles cooler
How is wind formed
Air moves from high to low pressure
what is the coriolis affect
the deflection of objects like wind due to the earth’s spin
What happens due to the Coriolis affect
Deflects wind to the right in the northern hemisphere (back where it can from) and back to the left in the southern hemisphere (back where it came from)
Define jet streams
High altitude currents of air
Define a tropical storm
Strong winds sustained over 74 miles per hour, moving in a spiral around the calm central area. Tropical regions have low pressure where rainfall is heavy. They usually occur in the tropics (mainly ITCZ) at low latitudes between 5-30 degrees, north and south of the equator
Describe the tropical storms that take place in the Atlantic ocean
hurricanes usually during august-october
generally from west to north west to north east with about 1-2 per year
describe the tropical storm which takes place in the indian ocean
cyclones during december-march
generally varies with hemispheres
describe the tropical storm that takes place in the pacific ocean
typhoons during may to december
Direction varies with hemispheres with about 3 per year
What are the characteristics of tropical storms
Warm, low-pressure systems with strong winds and heavy rain. They spin clockwise and form over warm ocean waters, impacting large areas with their high winds, rain, and storm surges.
Why do tropical storms happen
Due to the influence of the Coriolis affect
How can we categorise tropical storms
Using the Saffir Simpson scale
What 4 things help cause a tropical storm
Ocean depth of 60-70m
Sea temperature above 27C
Low wind shear
Not along the equator
What is the effect of ocean depth and sea temp in causing tropical storms
This provides the heat and moisture that causes air to rise rapidly. Latent heat is released which powers the storm
Define latent heat
Latent heat is the energy that is transferred to a substance without the substance’s temperature changing.
How does low wind shear cause a tropical storm
Winds which remain constant and do not vary with height allow the tropical storms to rise to high levels without being torn apart
How does the tropical storm not being along the equator help it form
The coriolis effect isn’t strong enough at the equator for it to spin, so needs to be somewhere else
What happens after a storm makes landfall
It soon dissipates - looses strength and fizzles out
Why does the tropical storm dissipate
There is no longer enough evaporation and energy occurring to fuel the storm
Describe the formation of a tropical storm
- The sun’s incoming solar radiation to Earth warms our oceans, most within the tropics.
- This warms the oceans to a critical 27°c
- This causes warm moist air to rise under low air pressure conditions
- strong winds form as more air is drawn upwards
- This air cools as it rises, at 1°c per 100m, this causes condensation to occur, Cumulonimbus clouds form and torrential rain occurs.
- The air starts to spin clockwise due to the coriolis effect
- Some cooled air sinks back down at the centre helping to create the calm central eye
- Air rushes in from higher pressure areas outside of the storm to lower pressure areas at the centre of the storm creating winds.
- The whole storm rotates because of the Earth’s spin.
How is the weather likely to change as the storm passes over a place
Increasing Winds: Winds will strengthen.
Heavy Rainfall: Intense rainfall leading to flooding.
Decreased Visibility: Due to cloud cover and rain.
Temperature Fluctuations: May decrease slightly during the storm.
Drop in Atmospheric Pressure: Before the storm and a rise afterward.
How might climate change affect the distribution of tropical storms
Distribution - significant/random areas of the globe experience tropical storms. This is because areas now have warmer oceans. The map shows that we will experience changes in the Power Dissipation index.
How might climate change affect the frequency of tropical storms
The total number of storms in the north Atlantic has increased. This is because there is more energy available in the atmosphere and ocean waters to fuel tropical storms more often. We have also seen an increase in the number of short duration storms.
How might climate change affect the intensity of tropical storms
There are more storm surges and greater damage to human property. This is because due to the rise in temperature, accumulated storm energy has increased causing stronger winds.
Define primary effects
The initial impact of a natural event on people and property, caused directly by it.
Define secondary effects
The after-effects that occur as indirect impacts of a natural event, sometimes on a longer timescale.
Suggest some primary effects
People injured/killed by debris blown around
Buildings are damaged or destroyed by debris or storm surge
People drown
Infrastructure + Services become contaminated
Suggest some secondary effects
If crops/food destroyed result in food shortage
People left homeless
Electric supplies cut off due to power destroyed
Sewage released due to flooding
Lack of clean water + sanitation can lead to disease
Transport networks blocked by debris making it hard to bring aid
Unemployment is caused by damaged businesses
Suggest immediate responses to tropical storms
People evacuated before storm lands
People who are trapped rescued
Provided medical support for injured people
Temporary shelters set up for homeless
Provided water and food for people
Dead bodies recovered
Aid provided by government
Suggest long term responses to tropical storms
properties re-build and repaired + peopled rehoused
Infrastructure and services repaired
Improved forecasting and early warning systems
Improve building regulations for properties to withstand impacts
Offer incentives such as tax breaks to encourage economic recovery
What factors affect the effectiveness of immediate responses and longterm response3s
Road conditions - transport
Intensity - amount of damage
Economic stability - LIC or HIC
Population - aging, amount
Relationships with other countries - aid
How does monitoring reduce the effects of tropical storms
Monitoring tropical storms reduces their effects by providing early warnings, enabling accurate track and intensity predictions, facilitating resource allocation, promoting public preparedness, and protecting infrastructure.
How does prediction reduce the effects of tropical storms
Intensity Forecasting: Predictive models also estimate the intensity of tropical storms, including factors like wind speed, rainfall, and storm surge potential.
How does protection reduce the effects of tropical storms
Reinforce building material, coastal defences, no building zones, Natural Buffer Zones- wetlands, mangroves, and dunes can mitigate the impacts of tropical storms by absorbing floodwaters, reducing erosion, and providing habitat for wildlife. These ecosystems act as natural barriers, dissipating wave energy and protecting coastal communities from storm surges and erosion.
vegetation cover
How does planning reduce tropical storm impacts
raise community awareness, education, disaster suppl kits, evacuation routes, fuelled vehicles
Formation of tropical storm
- Air on the surface of ocean warmed
- Warm moist air rises under low pressure conditions
- Strong winds form as more air is drawn upwards
- The air starts to spin clockwise due to the coriolis affect
- Rising air cools and condenses to form cumulonimbus clouds which release torrential rain
- Latent heat is released outwards which powers the storm
- Cold air sinks down the centre of the storm creating the calm central eye
- Prevailing winds push the storm towards land (tracks north in the northern hemisphere and south in the southern hemisphere)
- When the storm reaches land it looses heat and moisture so dissipates (fizzles out do to the loss in energy)
