Weather Unit Flashcards
What is weather?
Weather is the day to day change in the state of the atmosphere at any given place and time
What are the factors that affect rainfall?
Relief (Height of the Land)
Aspect
Distance from the Sea
What are the factors that affect temperature?
Relief ( Height of the Land)
Aspect
Distance from the sea
Latitude
Explain how relief affects rainfall?
Upland areas receive more rain than lowland areas.
Explain how the aspect of the land affects rainfall?
West facing hillsides receive more rain as these slopes face the Atlantic Ocean where the moist air is coming from. Fewer clouds on leeward (east) side so less rain.
Explain how the Distance from the sea affects rainfall?
Most of the water vapour in our air has evaporated from the Atlantic Ocean. Winds reach the west coast carrying a lot of moisture therefore bringing rain. As winds move eastwards they drop their water so they bring less rain to places further east.
Explain how relief affects temperature?
everytime you gain 100m in altitude you lose 1 degree in temperature. aka Being in Inverness is warmer than being up Ben Nevis.
Explain how aspect of the land affects temperature?
places that face south are generally warmer than places that face north - this applies to the Northern Hemisphere Only, it would reverse if in the southern Hemisphere-
Explain how Distance from the sea affects temperature?
A warm ocean current called the North Atlantic Drift makes the temperature even milder, particularly in western areas. ( Warmer in winter,colder in summer)
Explain how latitude affects temperature?
Latitude affects temperature as at the equator the the sun’s rays are direct (concentrated) - hence why it is the hottest part of the planet- The further away from the equator you get the more area the sun’s rays have to heat up. ( Think about an iphone torch being shone directly down onto the table and then moved to light up something further away from you - see how the light expands-)
Describe how a long period with a Tropical Continental air mass in Summer would affect the people of the British Isles?
Tropical continental air mass will bring hot dry weather in summer which could result in Droughts.There might need to be hose-pipe bans. Grass might wither and die causing problems for livestock farmers.Ice cream sales might rise as people make the most of the sunny weather and head to the beach.Could be very hot and difficult to do Physical work outside.People will be more likely to suffer from heat stroke and sun burn.
Describe the problems which an Arctic Maritime air mass is likely to bring to Northern Scotland in Winter?
There could be heavy snowfalls which could cause roads to be blocked or cause traffic accidents due to snow and ice on main roads. Cold temperature might cause icy pavements which could be dangerous especially to the elderly. Livestock could die due to extreme conditions. Pipes in people’s homes can freeze and crack causing damage to property.
what is air pressure measured in?
Millibars
What are depressions?
Depressions are areas of low atmospheric pressure caused by rising air. The rising air causes clouds to form, typically leading to rainy weather.
What are anticyclones?
Anticyclones are areas of high atmospheric pressure, where the air is sinking. They bring dry and settled weather. (Temperature varies with the seasons)
What is it called when two air masses meet?
Front
How is a cold front signified on a synoptic chart?
Blue line with triangles
How is a warm front signified on a synoptic chart?
Red line with semi circles
How is an occluded front signified on a synoptic chart?
Purple line with mix of triangles and semi circles
What type of weather does a cold front bring?
Heavy rain
What type of weather does a warm front bring?
Rain
What type of weather does an occluded front bring?
Very heavy rain
What direction do fronts move?
West to east
Describe a Front
Each front is really a broad band of cloud
Each front usually brings rain as it passes
The air between the warm and cold front is known as the WARM SECTOR and brings warm air
Everywhere else is the COLD SECTOR and brings cold air
The weather at any place in it’s path will change as the front passes over it.
Describe the Isobars when they are signifying a depression
Isobars decrease as you move towards the centre of the depression
Wind blows inwards/anti clockwise around a depression
The closer the isobars the stronger the winds
The further apart the Isobars are the gentler the winds
Describe a Depression
Depressions pass over the UK from WEST to EAST and they are formed over the ATLANTIC ocean. Air pressure is lowest at the centre of a depression, typically below 1000 mb. Winds blow in an ANTI-CLOCKWISE direction towards the centre of a depression. If the Isobars are close together, this means winds will be strong. Depressions carry FRONTS which bring cloud and RAIN. The WARM front passes over first followed by the warm SECTOR. This is then followed by the COLD front which brings heavy rain. If the cold front catches up with the warm front and occluded front is formed.
What are the features of an Anti-Cyclone?
AntiCyclones bring SETTLED weather to the UK. Air pressure is HIGH at the centre of an anticyclone, typically over 1000mb. Winds blow in a CLOCKWISE direction outwards from the centre of an anticyclone. As the ISOBARS are far apart, this means winds will be LIGHT. Therefore anticyclones move more SLOWLY than depressions. As anticyclones do not carry CLOUDS there will be CLEAR skies and SETTLED conditions.
What type of weather does an anticyclone bring in summer?
High temperatures, Clear skies, Calm or light winds, No precipitation
What type of weather does an anticyclone bring in Winter?
Low temperatures at night which could lead to temps below freezing producing frost.
High humidity which can produce persistent fog
Clear skies
Calm or light winds
No precipitation
What is the Source Area and Weather Characteristics of a mT air mass?
Source Area - Atlantic Ocean
Weather Characteristics - Warm and Wet
cT air mass Source Area and Weather Characteristics
Source Area - Southern Europe and North Africa
Weather Characteristics - Warm and Dry
mP air mass Source Area and Weather Characteristics
Source Area - North Atlantic Ocean
Weather Characteristics - Cold and Wet
cP air mass Source Area and Weather Characteristics
Source Area - Northern Russia
Weather Characteristics - Cold and Dry
mA air mass Source Area and Weather Characteristics
Source Area - Arctic Ocean
Weather Characteristics - Very cold - can bring heavy snow in winter
What type of Weather does an AntiCyclone Bring in Summer?
High Temperatures
Clear Skies
Calm or Light winds
No precipitation
What type of weather does and anticyclone bring in Winter?
Clear skies
Calm or Light Winds
No precipitation
Low temperatures at night which could lead to temps below freezing, producing frost.
High humidity which can produce persistent fog
What are the Advantages of a High Pressure system/Anticyclones?
People can Sunbathe
People visit beaches/Swim in sea
Ice Cream Sales Increase
BBQ food Sales Increase
What are the disadvantages of A High Pressure system/Anticyclone?
- High pressure in Winter causes ice and foggy conditions. This can cause car accidents and people slipping on ice and breaking bones, especially the elderly.
- Drought - Water bans/Hose pipe bans
- Grass and crops wither and die
- Farmers lose crops and lose profit
- People suffer from heat stroke especially the elderly
- Can lead to an increase in long term skin cancer diagnoses
- Can lead to accidents in Open seas
- More people will be ‘out and about’ and therefore increases the chances of infectious disease spreading
What are the Advantages of Low pressure systems/Depressions?
- No Irrigation Needed
- Crops can grow well
What are the disadvantages of Low pressure systems/Depressions?
- Flooding
- Crops can be destroyed
- Storms- Powerlines can be destroyed, accidents can happen
