Chapter 5 Flashcards
Temperature Anomaly
is a difference, or irregularity, found by comparing recorded average annual temperatures against the long term annual temperature
For each celsius degree of global temperature increase:
- 5-10% changes in precipitation in many regions
- 3-10% increases in amount of rainfall during heaviest precipitation events
- 5-10% changes in flows of streams and rivers
- 25% decreases in extent of Arctic summer sea ice
- 5-15% reduction in crop yields
- 200-400% increases in the area burned by wildfire in some areas of the western United States
Heat Wave
is a prolonged period of abnormally high temperatures, usually, but not always, in association with humid weather
Heat Stress in Humans
significant proportion of humans live in mid-latitude locations where heat waves will increase
symptoms:
- heat cramps
- heat exhaustion
- heat stroke
- old people and young people have a harder time regulating their average internal temperature
Humidity
the presence of water vapour in the air. It is commonly expressed as relative humidity
Why is perspiration not as effective a cooling method in humid environments
In humid conditions, the air cannot absorb as much moisture, so perspiration is not as effective a cooling mechanism as in dry environments.
Heat is gained by:
absorption of energy
Heat is lost by:
emission of energy
What is temperature a measure of?
the average energy of motion of molecules in an object
Temperature Scales
- Fahrenheit
- Celsius
- Kelvin
Absolute zero
The temperature at which atomic and molecular motion in matter completely stops
Daily Mean Temperature
- 13°C
Monthly Mean Temperature
-15°C
The most important influence on temperature variations on Earth:
Insolation
Physical influences on Earth’s temperature patterns
- insolation
- latitude
- altitude and elevation
- cloud cover
- land–water heating differences
Physical Influence of LATITUDE on Earth’s temperature patterns:
- insolation is more intense between the tropics than at higher latitudes where the Sun is never directly overhead (at a 90° angle) during the year
- Change of sun angle (declination) and day length throughout the year drive the seasonal effect of latitude on temperature
Physical influence of ALTITUDE AND ELEVATION on Earth’s Temperature patterns:
- density and temperature within the troposphere decreases with increasing altitude
- as the atmosphere thins, it contains less sensible heat
worldwide - Mountainous areas experience lower temperatures than do regions nearer sea level, even at same latitudes
which way does heat flow?
heat flows from matter at a higher temperature to matter at a lower temperature
Altitude
the height of an object or point in relation to sea level or ground level
refers to airborne objects or heights above Earth’s surface.
Elevation
usually refers to the height of a point on Earth’s surface above sea level
Physical influence of CLOUD COVER on Earth’s Temperature patterns:
- clouds affect the earth– atmosphere energy balance (by reflecting and absorbing radiation)
- effects vary with (3) cloud type, height, and density
At any given moment, approximately __% of the Earth is covered by clouds
50%
What effect does cloud cover have on temperature at night?
- Cloud cover during the night acts as an insulting layer that reradiates long-wave energy back to earth, preventing rapid energy loss to space.
- Raises minimum night-time temperatures
- A moderating effect
What effect does cloud cover have on temperature during the day?
Cloud cover during the day reflects insolation, lowering daily maximum temperatures
Clouds also reduce _______ ___________ __________ as a result of these moderating effects.
seasonal temperature differences
Physical influence of LAND- WATER HEATING DIFFERENCES on Earth’s Temperature patterns:
(5)
- Land and Water respond differently to insolation.
- Land and Water absorb and store energy differently.
- Water bodies tend to have more moderate temperature patterns
- Continental interiors have more temperature extremes.
- Land heats and cools faster than water
Factors that lead to LAND-WATER HEATING DIFFERENCES include:
(4)
- Evaporation
- Transparency
- Specific Heat
- Ocean Currents & Sea Surface Temperature
How is EVAPORATION a factor in LAND-WATER HEATING differences?
- Evaporation dissipates significant amounts of the energy arriving at the ocean’s surface (much more than over land surfaces)
- as water evaporates, it changes from liquid to vapour, absorbing heat energy in the process and storing it as latent heat
- as surface water evaporates, it absorbs energy from the immediate environment, resulting in a lowering of temperatures
- remember that the water and vapour remains the same temperature through-out the process; the vapour stores the absorbed energy as latent heat.
- Land temperatures are affected less by evaporative cooling than are temperatures over water
~ __% of all evaporation on Earth is from the oceans
84%
How is TRANSPARENCY a factor in LAND-WATER HEATING differences?
- Soil and water differ in their transmission of light:
- Solid ground is opaque; water is transparent
[[ - Light striking a soil surface does not pass through, but is absorbed, heating the ground surface.
so. … energy is accumulated during times of sunlight exposure and is rapidly lost at night or when shaded
- Light striking a body of water penetrates the surface and passes through.
so. … the distribution of available heat energy occurs over a much greater depth and volume, forming a larger reservoir of energy storage ]]
Describe what happens when light strikes a soil surface
Light striking a soil surface does not pass through, but is absorbed, heating the ground surface.
- energy is accumulated during times of sunlight exposure and is rapidly lost at night/when shaded
Describe what happens when light strikes a body of water
- Light striking a body of water penetrates the surface and passes through.
- the distribution of available heat energy occurs over a much greater depth and volume
- forming a larger reservoir of energy storage
How is SPECIFIC HEAT a factor in LAND-WATER HEATING differences?
(5)
- energy needed to increase the temperature of water is greater than for an equal volume of land
- water can hold more heat than can soil or rock
- a given volume of water represents a more substantial energy reservoir than does the same volume of soil or rock
- water consequently heats and cools more slowly
- day-to-day temperatures near large water bodies tend to be moderated rather than having large extremes
How is MOVEMENT a factor in LAND-WATER HEATING differences?
- Land is solid and water is fluid
- movement of currents results in a mixing of cooler and warmer waters
- mixing distributes energy throughout the oceans and large lakes
- Surface water and deeper waters mix, redistributing energy in a vertical direction as well
- Ocean and land surfaces radiate long-wave radiation at night, but land loses its energy more rapidly
How are OCEAN CURRENTS AND SEA-SURFACE TEMPERATURE factors in LAND-WATER HEATING differences?
- Ocean currents affect land temperatures in different ways, depending on whether the currents are warm or cold
- midlatitude and subtropical west coasts of continents
cool ocean currents flowing toward the equator - they moderate air temperatures on land
- Higher ocean temperatures produce higher evaporation rates, and more energy is dissipated from the ocean as latent heat.
Marine (maritime) effect
refers to the moderating influences of the ocean and usually occurs in locations along coastlines or on islands
Continental effect / Condition of continentality
refers to the greater range between maximum and minimum temperatures on both a daily and a yearly basis that occurs in areas that are inland from the ocean or distant from other large water bodies
Average internal Temperature for humans
36.8°C
