Week 6 - Drivers of Climate & Weather Flashcards
What is Climate? What is Weather?
Climate - is the long-term average atmospheric conditions and extremes (temperature, humidity, pressure) of a particular region
Weather - the short term highly variable atmospheric conditions of a particular region
Why do we have different biomes? (rainforest, desert, grassland and temperate forests)
Why is Melbourne’s climate different to Perth?
List some basic conditions in Climate/Weather
- atmospheric pressure measured in millibars (mb)
- isobars represents locations of equal pressure
- Mean s.I : 1013 mb
- Pressure Gradient Force (PGF) - generated when pressure differences occurs over surface (winds- from high to low)
What is Coriolis effect on PGF?
PGF - air moving from high pressure to area of low pressure
Coriolis effect (on winds) is a deflection - the Earth’s rotation causes winds to be deflected
Norther Hemisphere - deflection to right
Southern Hemisphere - deflection to left
Strongest - at poles
Weakest - at equator
Explain Differential Heating
Differential heating of the Earth
- greatest receipt of solar generation is along equator, less at the poles
- Latitudinal gradient in energy absorption = pressure gradient
- effect of albedo (reflective effect of Earths surfaces)
- textures of surface areas (ice, dark wet soil) affects the absorption of reflection of solar radiation/energy
Reason for seasonal variation.
- due to Earths rotation
- curvature of the Earth, tilt of the Earth
- higher latitude = greater seasonality
What is a Solstice? What is Equinox?
Solstices - times of maximum or minimum sunlight (summer and winter)
Equinox - times of equal sunlight and darkness (autumn & spring)
Discuss Seasonality
Name the 3 cells for each hemisphere
*Inter Tropical Convergence Zone (ITCZ) - maximum zone of internal heating, can vary due to landmass and oceans
Hadley Cell - driven by heat at equator, rising moist air at equator, descending cool dry air at tropics (pole end), stable weather
Polar Cell - driven by your arctic cold land mass, a heat sink (the air is chilled and descends), stable weather
Ferrell Cell - driven by the other 2 cells, the ball bearing in the middle, zone with a lot of exchange of energy, unstable weather (different pressures, weather cells moving through)
- the cells will change their position based on northern hemisphere and southern hemisphere
What is Continental tendency?
Tendency of land to experience more thermal variation than water due to the land’s lower specific heat capacity
- tends to be dryer than oceanic (maritime) climate as there is less moisture input to the atmosphere from evaporation
What is a monsoon?
Seasonal shift in regional prevailing winds that bring distinct changes in weather (wet & dry) - driven by continental scale temperature and pressure differences (ITCZ)
moved by pressure gradients
What is a oceanic current?
It redistributes heat e.g. cold water from deep to surface, absorbing heat from atmosphere
Driven by atmospheric circulation - winds
Distorted by landmasses - bounded, water cant travel over the land
It is a latitudinal and horizonal heat transfer
The Great Ocean Conveyor Belt
- major global heat distribution system
- interactions between oceans and atmosphere; climate and weather also affected
Discuss Organic Rainfall
- The Earths surface ranges up to 9km in elevation
- this OROGRAPHIC EFFECT produces uplift = vertical temperature variation
*The effect of topography of an area determines the climate of any area, determines rainfall
What is a Biome?
Biome - encapsulates the fundamental relationship between climate (temperature and precipitation) and vegetation
A definable geographic area classified and mapped according to:
- predominant vegetation and organisms
- of the particular environment (climate dominant)
- each biome is a distinct ecosystem with particular plant, animal and microorganism communities linked by energy and nutrient flows
i.e. different biomes have different system “settings” primarily controlled by climate
List types of Biomes
The five main groups are A (tropical), B (dry), C (temperate), D (continental), and E (polar).
Tropical Rainforest, Temperate Forest, Desert, Tundra, Boreal Forest or Taiga, Grassland, Savannah, Freshwater and Marine
Describe Tropical Climate
A tropical climate has warm temperatures throughout the year and a significant amount of precipitation.
Example: Tropical Rainforest
Describe Dry climate
Dry climates are areas that are very dry and where the water escapes and leaves the area drier than other places. Most dry climates have summers that are very hot, winters are cool and warm, and the air is very dry.
Describe Temperate climate
The Temperate climates have relatively moderate and mean annual temperatures.
Most of the regions coming under the temperate climate present four seasons, while the temperatures can change majorly between the summer and winter.
Example:
Temperate forests - are characterized as regions with high levels of precipitation, humidity, and a variety of deciduous trees.
- deciduous trees are trees that lose their leaves in winter.
- decreasing temperatures and shortened daylight hours in fall mean decreased photosynthesis for plants.
Describe Continental climate
a relatively dry climate with very hot summers and very cold winters, characteristic of the central parts of Asia and North America
Describe Polar climates
A polar climate is one that is characterized by the presence of ice in Antarctica. Climates that are characterized by low temperatures during the month of July and therefore do not experience warm summers are called polar climates
What is an Epiphyte?
A plant that grows on another plant, especially one that is not parasitic, such as the numerous ferns, bromeliads, air plants, and orchids growing on tree trunks in tropical rainforests.
