Geo1000 test 3

weather

the state of the atmosphere at a given time in relation to meteorological phenomena

climate

The meteorological condition of an area in general over a long period of time

climate normals occur in what timespan

30 year timespan.

weather is known as the current state under…

Parameters

Net radiation equation

Rn = Q (down) - Q (up ) - I (up) + I (down)

Q (down)

incoming shortwave radiation from the sun (insolation)

Q(up)

reflected shortwave radiation from earth (albedo)

I (up)

longwave radiation radiated by the earth

I (down)

longwave radiation reflected back towards the earth

what is the principle heat source at earths surface

solar energy

solar energy inputs

diffuse and direct radiation

solar energy outputs

evaporation, convection, and radiated longwave energy

diffuse solar energy

obstructed light, caused by things like cloud

direct radiation

sunlight minus any inhibition

what surfaces are more reflective

light colored surfaces like deserts and snow

energy budgets at specific places or times on earth are …

not always the same

energy surplus in the tropics

more energy is gained than lost

energy deficits in the polar regions

more energy is lost than gained

… amounts of longwave radiation are … over polar regions and the tropics

lesser amounts are lost

… amounts of longwave radiation are … from subtropical deserts

Greater amounts are lost

what drives the global circulation pattern

the imbalance of energy from the tropical surpluses and the polar deficits

global circulation pattern

movement of air/weather

latitudinal imbalances are due to

points closes to and furthest from the sun

vernal/autumnal equinox day

March 21/Sept22

Summer solstice day

June 21

winter solstice day

dec 21

winter solstice hours of daylight where

12 hr daylight at 0 degrees

0hr daylight at N pole

summer solstice hours of daylight where

24 hr daylight at N pole

12 hr daylight at 0 degrees

vernal/autumnal equinox hours of daylight

12 hr daylight at 0 degrees

sun rising/setting at the N pole

incoming energy time patterns

Incoming energy arrives during daylight, beginning at sunrise, peaking at noon, and ending at sunset

air temperature peaks at what point in the day

between 3:00 and 4:00 PM

lowest point of air temperature

right at or slightly after sunrise

warmest time of the day occurs not

at the moment of maximum insolation

when does the warmest time of the day occur

when a maximum of insolation has been absorbed and emitted from the ground

The annual pattern of insolation and air temperature exhibits

exhibits a similar lag

microclimatology

science of physical conditions, including radiation, heat, and moisture

Net radiation (NET R OR Q*)

sum of all radiation gains and losses at any defined location on Earth’s surface

sensible heat

is the heat transferred back and forth between air and surface in turbulent eddies through convection and conduction within materials

ground heating and cooling

is the flow of energy into and out of the ground surface by conduction

latent heat of vaporization

energy that is stored in water vapor as water evaporates

planetary boundary layer means…

energy and moisture are continually exchanged with the lower atmosphere at Earth’s surface

latent heat of fusion

ice → water

latent heat of vaporization

water → steam

when does heat transfer downward

during the day

when does heat transfer upward towards the surface

at night

how does the ground heat and cool

by conductuon

net heat transfer into the surface by day

Q (up) = K (up) + L(up)

net heat transfer by night

Q (up) = L (up)

when Q* is positive there is

a radiation surplus, and energy will flow away from the surface

Qh

a convective sensible heat flux into the air

Qe

a convective latent heat flux into the air

Qg

a conductive sensible heat flux into the surface

Qh and Qe both depend on…

wind to carry heat away from the surface

Non radiative heat transfer formula

Q (up) = Q (down) H + Q (down) E + Q (down) G

non radiative heat transfer in dry conditions

the energy surplus is divided into QH and QG

– The temperature of the ground and the air near the surface will both rise

Partition of energy into the two fluxes depends on the relative ease of the fluxes which are

– Surface conductivity versus wind speed

– Ground typically has a low heat conductivity

– Most of the surplus goes into QH

non radiative heat transfer in moist conditions

there is an additional partition into evaporation Qe

partitions in evaporation in moist conditions

– The larger QE is, the less the temperature will rise

– The partition depends on the availability of moisture

plants control Qe by controlling

transpiration, water is drawn up through the roots and lost through stomata

non radiative heat transfer by day

– Q* is positive

– Ground and air become warmer

– Water vapour in the air increases

non radiative heat transfer by night

– Q* is negative

– Ground and air become cooler

–Water vapour decreases; there is condensation into dew or sublimation into frost

desert surface Q*

Is low due to high albedo

desert surface temperature increase during the day is large due to

Low specific heat

– Little moisture for evaporation

– Low heat conductivity

desert surface L (up) is also high due to

large temp decrease at night

clear skies in dry conditions

ocean surface Q*

high due to low albedo

ocean surface temperature increase during the day is low due to

– High specific heat

– Lots of evaporation

– Convective mixing carries heat deeper into the water

ocean surface L (up) is low due to

small temp decrease at night

7 elements of climate

temperature

precipitation

wind speed

wind direction

relative humidity

evaporation

insolation

temperature varies in

mean, diurnal and seasonal amplitude, annual variability (apply to other elements too)

temperature is a measurement of

average kinetic energy

temperature influences

precipitation

air temp measured by a thermometer is a result of its

energy balance

to avoid erroneous temperature measurements..

• Use shielding to avoid radiative exchange

• Enhance convective exchange with fans

• Build very small sensors

precipitation

Moisture that falls from the sky (Amount and Duration)

liquid precipitation

drizzle, rain, dew, fog

solid precipitation

snow, hail, sleet, freezing rain, hoar frost

wind is the….

the horizontal movement of air (Advection) due to unequal heating of the surface.

wind influences

temperatures, evaporation, snow distribution & other factors

why does wind travel

pressure gradients from an area of high pressure to low pressure

relative humidity is the ratio of

water vapor in the air compared to the maximum water vapor the air could hold at that temperature

relative humidity affects

temperatures and environments

humidex relates…

Relates sensed heat to temperature and relative humidity

more discomfort with.. humidity and … wind

high humidity low wind

lethbridge has no trees why

low precipitation, more precipitation at river bottom

humidex is a capacity of….

how much the air can hold, dictated by heat

evaporation needs

heat, dry air, water

evapotranspiration

evaporation and transpiration

types of evaporation

potential vs actual

evapotranspiration is associated with … and has what effect

latent heat and a cooling effect

insolation is aka

cloudiness

insolation effects how much…

direct sunlight is received

cloudiness affects what as a result of sunlight receival

temperatures and evapotranspiration

insolation depends on

moisture

insolation can affect what in an environment

types of plants

parts of an anemometer

• radiation sensor

• rain gauge

• l-button stake for snow depth

• radiation shield for temp and relative humidity sensor

• evaporation can be calculated

7 influences on climate

1. latitude

2. effects of altitude/elevation

3. distribution of land and sea

4. nature of ocean currents

5. distribution of mountain barriers

6. pattern of prevailing winds

7. location of main centers of high and low pressure

latitude effects climate how

affects insolation

effects of altitude/elevation on climate

Temperatures are colder at higher elevation*:

A rising air parcel expands (less pressure) – this expansion consumes energy & the air parcel cools.

exception to the elevation rule

inversions