Lecture 2: Climate Flashcards
Basic unit of temperature
Kelvin
combination of temperature, humidity, precipitation, wind, cloudiness, and other atmospheric conditions occurring at a specific place and time
weather
the long-term average pattern of weather and may be local, regional, or global
climate
the amount of evaporation in the air
humidity
formula of celsius
oC=5/9 (oF-32)
formula of Fahrenheit
oF = 9/5 (oC) + 32
formula of Kelvin
K = 273 + oC
the Study of the Relationship between Organisms and Their Environment
Ecology
Organisms Interact with the Environment in the Context of the
__
Ecosystem
Ecological Systems Form a __
Hierarchy
Ecologists Investigate Nature Using the __
Scientific Method
the electromagnetic energy emanating from the Sun
Solar radiation
travels more or less unimpeded through the vacuum of space until it reaches Earth’s atmosphere.
Solar radiation
unit for wavelength
lambda
A portion of the electromagnetic
spectrum, separated into __ and __.
solar (shortwave); thermal
(longwave) radiation
represent only a small part of the
electromagnetic spectrum
- Ultraviolet
- visible
- infrared light waves
unit for frequency
v
The hotter the object is, the __ the emitted photons and the
__ the wavelength
more energetic; shorter
The wavelength of radiation emitted by an object is a __. The Sun, with an average surface temperature of __, emits __ as compared to Earth, with an average surface temperature of __, which emits __.
- function of its temperature
- 5800°C; shortwave radiation
- 15°C; longwave radiation
Some of the shortwave radiation that reaches the surface of our planet is __.
reflected back into space
The quantity of shortwave radiation reflected by a surface is a function of its reflectivity, referred to as its ___
albedo
expressed as a proportion (0–1.0) of the shortwave radiation striking a surface that is reflected and differs for different
surfaces.
albedo
albedo of surfaces covered by ice and snow
0.8–0.9
albedo of forests
0.05
The global annual average albedo is approximately __
0.30
a measurement from of how reflective a surface is.
albedo
albedo of white paint
0.80
albedo of asphalt
0.10
albedo of grass
0.25
*Black objects have an albedo of __.
* Less than __ of __ is reflected.
- <0.1
- 10%
- infrared energy
- White objects have an albedo of __.
- More than __ of infrared energy is
reflected
- > 0.8
- 80%
Ocean water has an albedo of about __.
0.06
Sea ice and glaciers have an albedo of about __.
0.6
equation of net shortwave radiation absorbed by the surface
Incoming shortwave radiation - reflective shortwave radiation = net shortwave radiation absorbed by the surface
some of the energy absorbed by Earth’s surface (both land and water) is emitted back out into space as __.
terrestrial longwave
radiation
The amount of energy emitted is dependent on the __ (the hotter the surface the __ will emit)
- temperature of the surface
- more radiant energy
- Most of the longwave radiation emitted by Earth’s surface is absorbed by __ and __ in the atmosphere
- This absorbed radiation is emitted downward toward the surface as __ (keeps surface temperatures warmer a.k.a. GREENHOUSE EFFECTcaused by GREENHOUSE GASES)
- water vapor
- carbon dioxide
- longwave atmospheric radiation
variable gases that can trap and re-radiate some heat back towards the Earth’s surface
greenhouse gases
examples of greenhouse gases
- Carbon dioxide (CO2)
- Nitrous oxides (NOx)
- Methane (CH4)
- Water vapor (H2O)
- CFC’s
It is the difference between the __ and __ that defines the net radiation and determines surface temperatures.
- incoming shortwave (solar)
radiation - outgoing longwave (terrestrial) radiation
__ is the difference between the amount of shortwave (solar) radiation absorbed by a surface and the amount of longwave radiation emitted back into space by that surface. LW, longwave; SW, shortwave
* give the equation
Net radiation
- Net radiation - (Incoming SW - Reflected SW) - (Emitted LW - Downward LW)
If the amount of incoming shortwave radiation exceeds the amount
of outgoing longwave radiation = __
surface temperature increases
if the quantity of outgoing longwave radiation exceeds the incoming shortwave radiation = __
* Example: __
- surface temperature decreases
- during the night
- On average, the amount of incoming shortwave radiation intercepted by Earth and the quantity of longwave radiation emitted by the planet back into space is __
- the average surface temperature of our planet remains approximately __
balanced; 15 degrees celsius
the global map of average annual surface shows that there is a distinct ___ from the equator toward the poles.
latitudinal gradient of decreasing net surface radiation
What are the factors influencing the variation latitudinal gradient of decreasing net surface radiation from the equator toward the poles?
- At higher latitudes, solar radiation hits the surface at a steeper angle, spreading sunlight over a larger area
- Solar radiation that penetrates the atmosphere at a steep angle must travel through a deeper layer of air
➢In the process, it encounters more particles in the atmosphere, which reflect more of the shortwave radiation back into space
As one moves from the equator to the poles, there is a __ in the average amount of solar (shortwave) radiation reaching Earth’s surface. Two factors influence this variation.
First, at __, solar radiation hits the surface at a __, spreading sunlight over a larger area than at the equator.
Second, __ that penetrates the atmosphere at a steep angle must travel through a deeper layer of air
- decrease
- higher latitudes; steeper angle
- solar radiation
The result of the decline in net radiation with latitude is a distinct __ from the equator toward the poles
gradient of decreasing mean annual temperature
- What gives rise to the seasons on Earth?
- Why do the hot days of summer give way to the changing colors of fall, or the freezing temperatures and snow-covered landscape of winter to the blanket of green signaling the onset of spring?
The tilt of the Earth (23.5 degrees)
Earth, like all planets, is subject to two distinct motions
rotation and revolution
While it orbits the Sun, Earth rotates about an axis that passes through the North and South Poles, giving rise to the brightness of day followed by the darkness of night
- the diurnal cycle
Earth travels about the Sun in an
ecliptic cycle
Earth’s axis of spin is not perpendicular to the ecliptic plane but tilted at an angle of __
As a result, as Earth follows its __ about the Sun, the location on the surface where the Sun is directly overhead at
midday migrates between __ and latitude over the course of the year
- 23.5 degrees
- elliptical orbit
- 23.5° N ; 23.5° S
Solar radiation falls directly on the Tropic of Cancer, with increased input and day length in the Northern Hemisphere
Summer Solstice (June 22)
Solar radiation falls directly on the equator
Vernal and autumnal equinoxes
Solar radiation falls directly on the Tropic of Cancer, with increased input and day length in the Southern Hemisphere
Winter solstice (December 22)
Note that as a result of the 23.5° tilt of Earth on its north-south axis, the point of Earth’s surface where the Sun is directly overhead migrates from the __ (23.5° N) to the __ (23.5° S) over the course of the year
- tropic of Cancer
- tropic of Capricorn
In the __, there is little seasonality (variation over the year) in net radiation, temperature, or day length
equatorial region
Seasonality systematically __ from the equator to the poles
increases
At the Arctic and Antarctic circles (66.5° N and S, respectively), day length varies from __ over the course of the year. The days shorten until the __, a day of continuous darkness. The days lengthen with spring, and on the day of the __, the Sun never sets
- 0 to 24 hours
- winter solstice
- summer solstice
- As we discussed in the previous section, the average net radiation of
the planet is __ - the amount of incoming shortwave radiation absorbed by the surface is
__ by the quantity of outgoing longwave radiation back into space. - Otherwise, the average temperature of the planet would either
increase or decrease - Geographically, however, __
- zero
- offset (balance)
- this is not the case
there are regions of positive
(__) and negative (__) net
radiation
- surplus
- deficit
the __ receives the largest annual input of solar radiation and the greatest net radiation surplus.
equatorial region
- Air warmed at the surface __ because it is __ than the cooler air above it
- Air heated at the equatorial region rises to the top of the
__, establishing a __ at the surface - This low atmospheric pressure at the
surface causes air from the north and
south to flow toward the __ - The resulting convergence of winds
from the north and south in the region
of the equator is called the
__, or __, for short
- rises; less dense
- troposphere; zone of low pressure
- equator
- Intertropical Convergence Zone; ITCZ
- The continuous column of rising air at the equator forces the air the mass above to spread __.
- As air masses move __, they cool, become __, and __
- The sinking air at the poles __ surface air pressure, forming a __ and creating a __ from the poles to the
__ - The cooled, heavier air then flows toward the __ at the equator, replacing the __ rising over the tropics and
closing the pattern of air circulation
- north and south toward the poles
- poleward; heavier (more dense); sink
- raises; high-pressure zone; pressure gradient; equator
- low-pressure zone; warm air
Earth, however, spins on its axis from
West to East (counterclockwise)
- Although each point on Earth’s surface makes a complete rotation every __, the speed of rotation varies with __
- At a point on the equator (its widest circumference at 40,176 km), the speed of rotation is __ per hour
- In contrast, at 60° N or S, Earth’s circumference is approximately half that at the equator (20,130 km), and the speed of rotation is __ per hour.
- 24 hours; latitude (and circumference)
- 1,674 km
- 839 km
- According to the __, the momentum of an object moving from a greater circumference to a lesser circumference will deflect in the __, and an object moving from a lesser circumference to a greater circumference will deflect in the __
- law of angular motion
- direction of the spin
- direction opposite that of the spin
- Air masses and all moving objects in the Northern Hemisphere are deflected to the __, and in the Southern Hemisphere to the __
- This deflection in the pattern of airflow is the __, named after the 19thc entury French mathematician __, who first analyzed the phenomenon
- right (clockwise motion)
- left (counterclockwise motion)
- Coriolis effect; G. C. Coriolis
- In addition to the deflection resulting from the Coriolis effect, air that moves poleward is subject to __, that is, poleward-moving air is forced into a __, and the density of the air __.
- These factors prevent a direct, simple flow of air from the equator
to the poles - Instead, they create a series of belts of __ , named for the direction they come from.
- These belts __ the simple flow of surface air toward the equator and they flow aloft to the poles into a series of __, __ in each hemisphere.
- They produce areas of low and high pressure as air masses ascend
from and descend toward the surface, respectively
- longitudinal compression; smaller space; increases
- prevailing winds
- break; six cells; three
Belts and cells of air circulation about a rotating Earth. This circulation gives rise to the __, __, and __ winds.
- trade
- westerly
- easterly
- The global pattern of __ plays a crucial role in determining major patterns of surface water flow in Earth’s oceans.
- These systematic patterns of water movement are called __.
- Each ocean is dominated by two great circular water motions or __.
- Within each gyre, the ocean current moves __ in the Northern Hemisphere and __ in the Southern Hemisphere
- prevailing winds
- currents
- gyres
- clockwise; counterclockwise
Notice how the circulation is influenced by the __ (clockwise movement in the Northern Hemisphere and counterclockwise movement in the Southern Hemisphere) and __, and how oceans are connected by currents.
- Coriolis force
- continental landmasses
Oceans with clockwise direction of current
- North Pacific
- North Atlantic
Oceans with counterclockwise direction of current
- South Pacific
- South Atlantic
- Indo-Oceanic
- Along the equator, trade winds push warm surface waters __.
- When these waters encounter the eastern margins of continents, they split into __ and __along the coasts, forming __and __.
- As the currents move farther from the equator, the __.
- Eventually, they encounter the __ at higher latitudes (30–60° N and 30–60° S), which produce __.
- When these eastward-moving currents encounter the western margins of the continents, they form __ that flow along the coastline toward the __.
- Just north of the Antarctic continent, ocean waters circulate __ around the globe.
- westward
- north-; south-flowing currents ; north; south gyres
- water cools
- westerly winds; eastward-moving currents
- cool currents; equator
- unimpeded (free)
Whenever matter, including water, changes from one state to another, energy is __.
either absorbed or released
(from the Latin latens, “hidden”) - the amount of energy released or absorbed (per gram) during a change of state.
Latent heat
In going from a more ordered state (liquid) to a less ordered state (gas), energy is __
* While going from a less ordered to a more ordered state, energy is __
absorbed; released
__, the transformation of water from a liquid to a gaseous state, requires __ of energy per gram of liquid water to be converted to __
-Evaporation
- 2260 joules (J)
- water vapor
__, the transformation of water vapor to a liquid state, __ an equivalent amount of energy.
Condensation; releases
- When air comes into contact with liquid water, water molecules are __ between the air and the water’s surface.
- When the evaporation rate equals the condensation rate, the air is said to be __
- In the air, water vapor acts as an independent gas that has __ and _.
- The amount of pressure that water vapor exerts independent of the pressure of dry air is called __ [defined in units of __].
- The water vapor content of air at saturation is called the __.
- freely exchanged
- saturated
- weight; exerts pressure
- vapor pressure; pascals (Pa)
- saturation vapor
pressure
- The saturation vapor pressure, also known as the __, cannot be exceeded.
- If the vapor pressure exceeds the capacity, ___ and __.
- Saturation vapor pressure varies with temperature, __.
- Having a greater quantity of thermal energy to support evaporation, warm air has a greater capacity for water vapor than does cold air
- water vapor capacity of air
- condensation occurs
- reduces the vapor pressure
- increasing as air temperature increases
equation of relative humidity
relative humidity = current vapor pressure/saturation vapor pressure x 100
- The amount of water in a given volume of air is its __
- A more familiar measure of the water content of the air is __, or the amount of water vapor in the air expressed as a percentage of the saturation vapor pressure.
- At saturation vapor pressure, the relative humidity is __.
- If the air cools while the actual moisture content (water vapor pressure) remains constant, then relative humidity __ as the value of saturation vapor pressure __.
- If the air cools to a point where the actual vapor pressure is equal to the saturation vapor pressure, moisture in the air will __.
- This is what occurs when a warm parcel of air at the surface becomes buoyant and rises.
- As it rises, it cools, and as it cools, the relative humidity increases.
- absolute humidity
- relative humidity
- 100 percent
- increases
- declines
- condense
