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Weather and Climate - Coggle Diagram

- - - - when the Earth surface gets heated up, water is converted to form water vapour through a process known as evaporation. as the warm air rises, it cools and once it reaches dew point temperature, which is the temperature at which saturation occurs, then condensation will occur assuming the water vapour has tiny particles to condense on, these particles are known as condensation nuclei. the water droplets together with the tiny particles will bump into each other and become larger in the process known as coalescence. this process will form clouds.
  - - - Convectional rainfall
        
        convectional rainfall occurs due to an intense heating up of the Earth's surface, it usually covers a small area of only a few square kilometers, and it heavy but short-lived, and accompanied by thunder and lightning. it usually occurs during late afternoons and evenings. Shortwave radiation from the sun reaches the Earth's surface and it gets intensely heated up. as a result, the air around the surface heats up, expands and rises. As the warm air rises, it reaches dew point temperature and condenses to form clouds. When the water droplets get too large and heavy, the water will fall as rain on Earth.
      - Relief rainfall
        
        Relief rainfall occurs when warm air is forced to rise up or above over a landform such as a mountain range. The warm moist air over the ocean is forced to rise up the windward side of a mountain, as it rises, it cools and once it reaches dew point temperature, it condenses to form clouds. when the water droplets get too large and heavy, it will fall as rain on the windward side. by the time the cloud moves over to the leeward side, the air is dry and no rainfall is observed.
- - - - Latitude refers to the distance of any point on the Earth that is North or south of the equator.
        These are imaginary lines that run East to west around the Earth and it is measured in degrees (the equator is at latitude 0, the North pole is at 90 N, the south Pole is at 90 S.) Each degree is 60 minutes.
      - Latitude is the most important factor affecting temperature, as latitude increase, the temperature decreases. This is because the Earth is tilted by its axis of 23.5°, this causes the sun rays to strike different parts of the Earth surface at different angles of incidences. At lower latitudes, the sun rays strikes the Earth surface perpendicularly, since the rays fall over a small area, the neat is more concentrated. As the Earth's surface is curved, the rays travel through a shorter distance of atmosphere at lower latitudes and thus less heat is lost through absorption, refection and scattering. Thus, at lower latitudes, higher temperatures are observed.
      - For example, in the North Pole (90°N) experiences long, cold winters and short cool summers with temperatures ranging from -40°C to 10°C. while in Singapore, at latitude 1°22N, experiences summer all year long with temperatures ranging from 23°C to 34°C.
    - - Altitude refers to the distance of a piece of land above sea level. As altitude increases, temperature decreases. For every 1000 metres increase in height, the temperature drops by about 6.5 degrees Celsius (Normal Lapse Rate). this is because at lower altitudes, the air is denser with more gases and particles, such as carbon dioxide, water vapour and dust, that can trap the long wave radiation that is reflected off the warm ground. Thus, causing the temperature at lower altitudes to be higher. at higher altitudes, the air is less dense with fewer gases and particles to trap heat, thus resulting in lower temperatures.
      - Solar energy from the sun reaches the Earth surface as shortwave radiation and about 45% of solar energy that reaches the Earth's surface is directly absorbed by the Earth's surface, causing it to heat up. The further up in the atmosphere we go, the further we are from the heated surface, and thus, temperatures will fall.
      - For example, at the base camp of Mount Everest, at an altitude of 5534m, has a temperature of -10 degrees celsius, while the peak of Mount Everest, at an altitude of 8488m, has a temperature of -30 degrees celsius
    - - Maritime effect
        
        the maritime effect refers to the effect that large water bodies have on the climate of coastal areas. It allows the coastal areas to experience a smaller annual temperature range. This is because during summer, the air over the sea is cooler than the air over the inland areas, due to the fact that the sea gains heat slower than land. Thus, the cooler air over the sea lowers the temperature of coastal areas. Thus, allowing coastal areas to experience cooler summers.
        
        During winter, the air over the sea is warmer than the air over inland areas, this is because the sea loses heat slower than the land. The warmer air over the sea increases the temperature in coastal areas, thus allowing coastal areas to experience warmer winters.
      - continental effect
        
        the continental effect refers to the effect that huge land masses have on the climate of inland areas, it allows the inland areas to have a larger annual temperature. Because the inland areas are further away from the seas, the temperatures are not regulated by the seas and thus, they experience warmer summers and colder winters.
      - For example, the village of Anchorage, 1km away from the sea has an annual temperature range of 20 degrees celsius, while the village of Fairbanks, 420km away from the sea, has an annual temperature range of40 degrees celsius.
    - - The extent of cloud cover refers to the extent of the sky that is covered with clouds, it is measured in eighths or oktas, and 1 okta is an eighth of the sky covered in clouds. Areas with thicker cloud cover have a lower diurnal temperature range than areas with thinner cloud covers.
      - In areas with little cloud cover, during the day, the incoming shortwave radiation from the sun is directly absorbed into the Earth's surface, causing it to heat up excessively, leading to very high temperatures. In the night, outgoing terrestrial longwave radiation escapes very quickly back into space, thus, temperatures fall by many degrees.
      - In areas with thicker cloud cover, during the day, the incoming shortwave radiation from the sun is reflected back to space by the clouds, thus the Earth's surface is not heated up excessively, leading to very low temperatures. In the night, the outgoing terrestrial longwave radiations are prevented from escaping back into space, thus, temperatures only fall by a few degrees.
      - For example, the Sahara Dessert can have diurnal temperature ranges as big as 30 degrees celsius due to the lack of cloud cover. During the hotter months, temperatures in the day can be as high as 55 degrees celsius and by night fall to below 0 degrees celsius. while equatorial areas like Singapore can have diurnal temperature ranges as small as 1.5 degrees celsius.
- - - - Wind speed
        
        Wind speed is measured in km/h and is measured using an anemometer or compared on the beaufort scale
      - Wind frequency
        
        Wind frequency is the number of times wind blows from a particular direction. Wind that blows the most frequently from a specific direction is known as the prevailing wind, and it is measured using a wind rose
      - Wind direction
        
        Wind direction refers to the direction from which wind blows and it is measured using a wind vane
    - - Local small-scale wind system
        
        Land breeze
        
        During the night, the sea cools down slower than the land, hence the air over the sea is warmer, expands and rises, forming an area of lower pressure. Over the land, the air is cooler and hence forms an area of higher pressure as the air remains at the surface. Since wind moves from a region of higher to lower pressure, a land breeze blows from the higher pressure area over the land to the lower pressure area over the sea.
        
        Sea breeze
        
        During the day, the land heats up faster than the sea, the air above the land heats up, expands and becomes less dense, and hence rises, creating an area of low pressure. The land over the sea is warmer, and hence the air remains at the sea surface, creating an area of high pressure. Since wind blows from a region of higher to lower pressure, a sea breeze will blow from the higher pressure over the sea to the lower pressure over the land.
        
        Small scale wind systems are small-scale local winds that can that are experienced at coastal areas, and this is due to the land and sea having different rates of heating and cooling
      - Regional wind systems
        
        Monsoon winds are large-scale regional wind patterns that alternates its direction seasonally. They are caused by the extreme heating and cooling of the land masses in relation to the seas, and this results in a difference in pressure and hence the movement of large-scale winds from a region of higher pressure to a region of lower pressure. The levels of precipitation can increase or decrease with the occurrence of monsoons and it mainly affects Asia, Australia
      - Coriolis effect
  - - - Temperature and pressure share an inverse relationship. This is because as temperature rises, molecules are further apart from each other, as a result of expansion, and will rise, thus there are lesser molecules per unit area, creating an area of low pressure. Conversely, at lower temperatures, molecules are closer to each other and become denser and sink, and since there is a larger number of molecules per unit area, pressure will increase
    - - Pressure and altitude share an inverse relationship. This is because at lower altitudes, there are more gas particles, and the air is denser, thus creating an area of higher pressure. On the other hand, at higher altitudes, there are fewer gas particles, and the air is thinner and less dense, hence creating an area of lower pressure.