Unitat 4
Solar radiation
Solar radiation is a continuous and unending energy source.
Solar radiation can be good or bad for humans.
● Beneficial: for domestic , humans health, industrial and agricultural uses.
● Harmful: for the eyes and skin disease, flora and fauna also will suffer
harmful consequences
Atmospheric temperature
Atmospheric temperature is a heating of air temperature as a result of solar
radiation.The sun’s rays are converted into heat when they touch the Earth's surface.
People feel warm or cold depending on the air temperature. The temperature directly
affects our physical wellbeing.
Measured in thermometers: measures the air temperature
Air humidity
Air humidity is the amount of water vapour in the air.
We can measure with a hygrometer: measures the air humidity in percentage (%).
Precipitation
Is the water that falls down to the Earth. Precipitation is when water vapour cools at
high altitudes and condenses into droplets that accumulate and from clouds. If they
cool down a lot, they can change into ice crystals. There are 3 types of precipitation:
rain, snow and hail. Rain is essential for all living things.
● Rain: Water drops bigger than 0,5 mm in diameter. The rain fall is measured
in mm using a rain gauge
● Fog: Small water drops , which remain near the ground and reduce visibility.
● Snow: small ice crystals.
● Dew: Condensation of water vapour in droplets caused by a sudden drop in
temperature or contact with cool surfaces
● Frost: A very thin layer of ice formed when water vapour freezes.
● Hail: Irregular-shaped balls of ice ranging from 5-50 mm in diameter.
Atmospheric pressure
Atmospheric pressure is the force of the air on the surface of the ground. It depends
on the altitude, air temperature and powerful air currents.
● Hot air: is light and not very dense, so it rises easily and creates areas of low
pressure, called depressions, less than 1015 hPa.
● Cold air: is heavier and more dense, so it tends to descend. It
creates high-pressure areas, called anticyclones, more than 1015 hPa.
Atmospheric pressure is measure in:
● Barometer: measures atmospheric pressure in hectopascals (hPa) = millibars
In a map the atmospheric pressure is measured in, isobars: lines that connect areas
with the same atmospheric pressure
Wind
Wind is a moving air mass and is caused when two places have different
atmospheric pressure. Air always goes from high pressure areas to low pressures
areas. The bigger the difference in pressure, the more intense the wind.
● Prevailing winds: always same direction
● Seasonal winds: depends on the season we are
● Local winds: depends on a specific area.
We can measure wind with:
● Anemometer: measures the speed of the wind in km/h.
● Weather vane: measures the wind direction.
Unitat 5
The temperature is different around the world. Factors:
● Latitude
● Altitude
● Distance from the sea
Latitude
Definition: The distance from 1 point to the Equator. At the Equator ,solar rays hit
the Earth at a very direct angle. The near you are from the Equator the hotter it is.
Consequence: climate zones
● Hot zone: Temperature very high (1)
● Temperate zone: Temperature between cold and hot (2)
● Cold zone: Temperature cold
Altitude
Definition: Is the height of a place on the Earth relative to sea level.
How: The higher you are the colder it is.
Distance from the sea
Definition: Depending the season you are and the farder or nearer the sea you are
is colder or hotter
Why: Because near the costal or the sea it’s milder.
Precipitation
Factors:
● Latitude: If you are nearer to the Equator it rains more
Why: The hotter it is the more water is evaporated.
Climate zones:
Hot zone: abundant
Temperate zone: depends
Cold zone: very low
● Altitude : The higher you go it rains more, the condensations it goes faster.
● Sea distance: near the cost it rains more.
Average annual rainfall (year)
More than 1000 mm, super wet
500-1000 mm, wet
250-500 mm, dry
less than 250 mm, super dry
Extreme zones
Hot Cold
1- Location: between tropics 1- Location: Polar circles ( N/S poles)
2-Temperature above 20 ºC 2- Temperature below 0ºC
(No seasons) ( no seasons)
3-Precipitation: more than 1000mm 3- Precipitation: low, usually snow
(abundant)
4- Types: 4- Types :
Tropical Polar
Equational Higher mountains
Dessert
Temperate climates
Location: temperate zone ( between hot and cold zones)
Temperature: average 15 ºC // seasons ( winter, spring summer and autumn)
Types of climates: oceanic, mediterranian and continental
