Flashcards in Chapter 5 Deck (38)
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
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
- heat cramps
- heat exhaustion
- heat stroke
- old people and young people have a harder time regulating their average internal temperature
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
The temperature at which atomic and molecular motion in matter completely stops
Daily Mean Temperature
Monthly Mean Temperature
The most important influence on temperature variations on Earth:
Physical influences on Earth's temperature patterns
- 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
- 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
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.
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
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:
- 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:
3. Specific Heat
4. 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