weather and climate Flashcards
what is weather
The day to day condition of the atmosphere including temperature, rainfall, sunshine and wind.
what is climate
The average weather conditions in an area over a prolonged period of time, around 30 years.
what are the elements of weather (7)
Sun Temperature Pressure Wind direction and wind speed Humidity Cloud type and cloud cover Precipitation
what is a stevensons screen (5)
Stevenson’s Screen: contains the thermometers
Painted white to reflect sun with double lid for insulation
Slatted sides to let the air circulate, but slanted downwards to prevent light getting in
Legs 1m long to prevent heating from ground
On short grass for same amount of reflection
how to measure sunshine
sunshine recorder
The number of hours and minutes of sunshine received at a place can be measured and recorded by a sunshine recorder.
This is a glass sphere partly surrounded by a metal frame. A strip of special card, divided up into hours and minutes, is placed below the sphere.
When the sun shines, the sphere burns the ray’s trace on the card and at the end of the day the length of the trace represents the amount of sunshine the location received
how to measure temperature
thermometer
Measures temperature degrees Celsius or Fahrenheit
Consists of a glass tube filled with mercury (or ink)
When the thermometer is warmed, the mercury expands pushing itself up the glass tube
When it is cool, it contracts moving back down towards the reservoir
The thermometers can be placed in a Stevenson Screen to make sure that the temperature is taken in a shady environment. This is a wooden box with slatted sides, a sloping roof and legs to keep the screen off the ground. It is painted white to reflect the sun.
how to measure air pressure
- barometer
Used to measure air pressure – the amount of pressure that is being subjected on the earth’s surface by the atmosphere above
Measures in millibars (mb)
Works by measuring how much a series of corrugated metal strips expand or contract
how to measure windspeed
anemometer
Measures wind velocity
Wind spins the cups on a shaft and a reading is given in meters per second
Usually used continuously to give an average wind speed
how to measure wind direction
wind vane
Measures the direction the wind is blowing in
Wind catches the thick end of the vane and spins the arrow towards the direction the wind is blowing
Needs to be situated in open ground, above the height of buildings/vegetation nearby
how to measure humidity
wet and dry bulb thermometers
Measure the humidity in the air
Consist of a regular thermometer (dry) and a wet thermometer
Dry air will absorb moisture from the muslin and cool the wet thermometer, moist air will not.
how to measure cloud type/cover
visual assessment
The ten main types of clouds can be separated into three broad categories according to the height of their base above ground
Cloud cover is measured in Oltas (eights) and is measured by a visual assessment of how much of the sky is covered in clouds
how to measure precipitation
rain gauge
Measures the amount of precipitation that has fallen in a give area
Must be placed in an open space to avoid runoff from vegetation/buildings
The funnel should be sunk into the ground to prevent evaporation from the sun
what are the climate zones
Polar Temperate Arid Tropical Mediterranean Mountains
what are the factors affecting climate
latitude pressure systems winds distance from the sea altitude ocean currents
how does latitude affect climate
Highest temperatures are recorded between the tropics (Cancer and Capricorn) 23.5 degrees north and south of the equator
As you move away from the equator, temperatures decrease
The Sun’s energy is more concentrated on or near the equator and becomes more dispersed as you move further north or south
The tilt of the earth and orbit throughout the year expand the warmest regions
how does pressure systems affect climate
Rising air at the equator causes a warm, wet climate
Descending air at the tropics causes dry, arid conditions
Temperate regions experience cold air descending from the poles and warm air from the tropics
The meeting of warm and cool air brings mild temperature and increased precipitation
how do winds affect climate
The prevailing wind is the most frequent wind direction a location experiences. In Britain the prevailing wind is from the South West, which brings warm, moist air from the Atlantic Ocean. This contributes to the frequent rainfall. When prevailing winds blow over land areas it can contribute to creating desert climates.
how does the distance from the sea affect climate
Land heats up and cools down quicker than the sea
Water takes longer to heat up than the land so in summer months, areas by the coast are cooled by the water
In winter, the opposite occurs – coastal areas are kept warmer as the sea loses temperature slower
Inland areas are more likely to experience extremes of temperature and increased temperature range
how does the altitude affect climate
Air temperature decreases as altitude increases
Air at sea level is under greater pressure and therefore denser. Denser air is able to hold more warmth
As you increased in altitude, air pressure drops and the air becomes thinner and cooler
For every 100m increase in altitude you can expect a drop in temperature by 1⁰C
how do ocean currents affect the climate
Warm ocean currents from lower latitudes warm cooler regions
Cold currents from polar regions can cool temperatures
Cold currents can increase aridity in certain areas
what is the latitude of equatorial regions and how does this affect the climate
- Close to the equator/on tropics
- closer to the equator = higher temperature
what is the wind amount of equatorial regions and how does this affect the climate
- low
- more humid and warm
what is the cloud amount of equatorial regions and how does this affect the climate
- heavy
- more rain and more humid
what is the humidity of equatorial regions and how does this affect the climate
-high
what is the pressure of equatorial regions and how does this affect the climate
- low
- strong convection
what is the mean temp. of hottest month for equatorial regions
25C
what is the mean temp. of coldest month for equatorial regions
25C
what is the annual temp range for equatorial
less than 5C
what is the rainfall amount for equatorial
more than 200mm
what is the rainfall distribution for equatorial
same throughout the year
what is the latitude of dry desert regions and how does this affect the climate
- Between 5° and 30° north and south of the equator
- on the tropics -> high temperature
what is the wind amount of dry desert regions and how does this affect the climate
- strong winds
- dry climate
what is the cloud amount of dry desert regions and how does this affect the climate
- almost none
- low levels of rain and humidity
what is the humidity of dry desert regions and how does this affect the climate
- low
- dry climate
what is the pressure of dry desert regions and how does this affect the climate
- high pressure
- fluctuating temperature
what is the mean temp. of hottest month for dry desert regions
30C
what is the mean temp. of coldest month for dry desert regions
18C
what is the annual temp range for desert
less than 5C
what is the rainfall amount for desert
less than 250mm
what is the rainfall distribution for desert
irregular
what is convectional rainfall
When the land warms up, it heats the air above it. This causes the air to expand and rise. As the air rises it cools and condenses. If this process continues then rain will fall. This type of rainfall is very common in tropical areas
what is relief rainfall
Prevailing winds bring warm, moist air to high areas
Air is forced to rise over high areas.
Air cools and condenses.
Clouds form and it rains.
Air descends on the other side of the mountains.
It warms up and therefore becomes drier.
what kind of rainfall does equatorial regions have
convectional rainfall
what kind of rainfall does desert regions have
relief (near highlands)
what are the natural vegetation characteristics of tropical rainforest ecosystem
Lianas: use large trees as support to reach sunlight
Fan Palms: wide leaved plants that capture as much sunlight & rainfall as possible
Buttress Roots: very long roots that support tall trees & suck up maximum amount of nutrients in poor soil
Drip tip leaves: leaves that let rainfall travel over them & drip to the ground, causing less damage by excess water
what are the soil characteristics of tropical rainforest ecosystem
Humus Layer: decaying biological matter; rainforest soil fertility is dependent on this
what are the wildlife of tropical rainforest ecosystem
Home to many mammals
Tigers in SE Asia
Jaguars in Central & South America
Leopards in Africa
Sloths
Primates
Lemurs
Home to birds, amphibians, reptiles & insects too
Animals adapt in differently to survive e.g. camouflage
what are the natural vegetation characteristics of hot desert ecosystem
Succulents: fat fleshy plants that store water in leaves, trunks and roots e.g. cacti
Ephemeral: plants with very short life cycles - typically 6-8 weeks; use very short wet seasons to pollinate
Long & wide roots: can absorb the maximum amount of rainfall, also aids stability in very loose soil
Spiky & waxy surface: protect themselves with spikes & wax so they are not eaten/damaged by animals
what are the soil characteristics of hot desert ecosystem
Thin layer of topsoil Low humus content Rocky – poor water retention Sandy – poor water retention Hard packed surface – poor infiltration Highly saline
what are the wildlife of hot desert ecosystem
Don’t have same variety as tropical rainforests
Many insects, reptiles and mammals adapt to survive
Nocturnal: animals hide in burrows or rocks & plants during hot daylight hours & only emerge at night
Camels: store fatty tissue in their humps which is later metabolized, releasing water & fat to survive in deserts
what are the effects of deforestation on the natural environment
Flooding: less interception by plants thus more flash floods
Landslides: removal of vegetation causes soil to become unstable
Biodiversity Loss: kills off unknown species, since they have no home
Less Photosynthesis: causes imbalance of O2 & CO2 in atmosphere
Silting: rivers & oceans are difficult to navigate due to reduced depth
Desertification: soil loses components vital to survival of plants
what are the reasons for deforestation
Farming: demand for food increases with population - need to clear more ground
Hydro-Electric Power: land may need to be removed to build dam
Mining: demand for resources increase – rainforests hold plenty
Road building: increased traffic requires roads – rainforests in the way
Settlements: cities are bigger with population – requires more land
Timber: used for biofuels and furniture
what are the effects of deforestation on people
Indigenous: people lose their homes & impacts their society
what are the layers of the rainforest
- emergent
- canopy
- understory
- shrub
what is emergent layer
tall trees up to 50m, few lower branches, grows above others to get full sunlight
what is canopy layer
trees 20-40m forming a continuous canopy, few lower branches, makes up 50% of vegetation
what is understory layer
The understory usually reaches about 12 meters. It receives only 2 to 15% of the sunlight that the canopy gets.
what is shrub layer
low shrubs & saplings, plants that adapt because they are extremely close to the forest floor
climate of sabah borneo (rainforest)
- jan -april : 200-300mm rainfall
- may-august : 350-450 mm
- september to december : 400-500mm
fauna sabah borneo
reticulated python
Pattern - the dark patterns of the reticulated python allow it to blend in with the shrubs on the forest floor or tree bark when gliding up trees
Strong, large body - the reticulated python kills its prey by constriction and suffocation so a large, strong body aids in holding the prey steady and suffocating it
Unhingeable jar - the python is known to eat prey as large as deer and on some occasions even humans. Its unchangeable jar allows it to swallow down large prey
flora sabah borneo
banana tree
Specialized underground storage organs to store nutrients and water, useful because banana trees have to compete for sustenance in a rainforest because of all the other plants
Large leaves for larger surface area to capture sunlight for photosynthesis
Strong roots that help it stay upright even with its heavy fruit
climate sahara desert
climate variability around borders, mainly due to topography and ocean currents, more tropical
fauna sahara desert
fennec fox
It is well known feature is its large ears, which has a large surface area helping the fox cool itself in the warm heat.
The fennec is the smallest breed of fox in the entire world. Its coat and ears have adapted to high-temperature and low supply of water within the large vast desert
The fox also has excellent hearing and is sensitive enough to hear prey moving even underground. It main supply of food is insects, small mammals, and birds
flora sahara desert
Sahara Olive tree
The Olive tree can survive on almost no water at all during the year. The Olive tree has shallow, exposed roots for collecting water.
Due to lack of abundant life in the Sahara Desert, the Olive tree is mainly self-pollinating.
