Climate

Question 1

troposphere

Answer 1

Lowest layer of Earth’s atmosphere (Earth’s surface -> approx 15km), contains majority of atmosphere’s mass (~80%) and where majority of weather occurs

Question 2

stratosphere

Answer 2

Atmospheric layer above the troposphere, containing ~20% of atmosphere’s mass, extending to about 50 km above the earth’s surface

Question 3

Shortwave radiation

Answer 3

Sun emits shortwave radiation (insolation)
Very hot object (only one: Sun) → shortwave radiation
Visible, UV, infrared, shorter wavelengths

Question 4

longwave radiation

Answer 4

Earth emits longwave radiation to the space
Cooler objects (everything else) → longwave radiation

Question 5

solar spectrum

Answer 5

A combination of visible, UV and infrared light from the sun, from 0 to over 2000 nano metres
There is a split between shortwave and longwave radiation

Question 6

solar constant

Answer 6

The rate at which energy reaches the earth’s surface from the sun which is about 1370 W m-2

Question 7

insolation

Answer 7

Insolation (incoming solar radiation)
Measured in units of watts per square meter (W/m2)
Varies mainly because variable ‘solar angle’

Question 8

global radiation

Answer 8

Global radiation is the total short-wave radiation from the sky falling onto a horizontal surface on the ground. It includes both the direct solar radiation and the diffuse radiation resulting from reflected or scattered sunlight.

Question 9

solstice solar angle

Answer 9

The angle at which the sun hits the Earth perpendicularly. This angle reaches a maximum angle 23.5 Degrees during the winter and summer solstices.

Question 10

Earth-Sun distance

Answer 10

Earth’s distance from the Sun: perihelion (nearest – Jan 3); aphelion (farthest - Jul 4). Variation in distance ~ 3.4 %.

Question 11

equinox

Answer 11

The equinox is a day where both day and night are equal with the sun vertical to at equator. Meaning 12 hours of daylight and 12 hours of darkness. Occurs twice a year. (sep 22-23 & mar 21-22)

Question 12

albedo

Answer 12

The proportion of short wave radiant energy scattered upward by a surface. It is an important property of a surface because it measures how much incident solar energy will be absorbed. “Reflectivity” 0-1

Question 13

radiation balance

Answer 13

The energy budget deals with how Q* (net allwave radiation is used). (i.e climate)

Question 14

urban vs. rural temperatures

Answer 14

Rural areas have more evapotranspiration and more Qe (water evaporated by convection) because we have a lot of leaves. There is less energy to heat the air and therefore the surface is cool.
Urban temperatures are warmer than rural areas because the energy is stored rather than consumed by process such as evaporation, transpiration as there is infrastructure and water is channeled resulting in dry surfaces. Heat stored in building materials is released at night

Question 15

urban heat island

Answer 15

Is a city that is significantly warmer than it’s surrounding rural areas due to human activities (CO2 emissions and buildings which absorb more heat during the day)
Heat island tends to persist over night
Parks reduce heat
Urban areas in deserts usually do not exhibit heat islands, where irrigated vegetation may make the city cooler

Question 16

continentality

Answer 16

a measure of the difference between continental and marine climates characterized by the increased range of temperatures that occurs over land compared with water.

Question 17

land and water contrasts

Answer 17

Land heats and cool quickly.

Water heats and cools slowly.

Question 18

greenhouse effect

Answer 18

The loss of energy from the earth is slowed down by greenhouse gases in the atmosphere. Thus, Earth is warmer than it would be without these greenhouse gases.

Question 19

atmospheric window

Answer 19

The infrared atmospheric window is the overall dynamic property of the earth’s atmosphere, taken as a whole at each place and occasion of interest, that lets some infrared radiation from the cloud tops and land-sea surface pass directly to space without intermediate absorption and re-emission, and thus without heating the atmosphere

Question 20

net radiation

Answer 20

Describes the balance between incoming and outgoing radiation. At latitude lower than 40 degrees, annual net radiation is positive, while it is negative at higher latitudes.

Question 21

cold front

Answer 21

Rapidly uplift warm fronts (as they are denser). Characterised by short periods of heavy rain; can involve lightening (due to rapid uplift), storms, or tornadoes.
Faster than warm fronts.

Question 22

mid-latitude cyclones

Answer 22

The mid-latitude cyclone is a synoptic (general) scale low pressure system that has cyclonic (counter-clockwise in northern hemisphere) flow that is found in the middle latitudes (not a hurricane or tropical storm).

Question 23

warm front

Answer 23

warm front

Question 24

occlusion

Answer 24

a process by which the cold front of a rotating low-pressure system catches up the warm front, so that the warm air between them is forced upwards off the earth’s surface between wedges of cold air.

Question 25

cyclogenesis

Answer 25

The development or strengthening of a cyclonic circulation in the atmosphere (a low pressure area)

Question 26

air mass

Answer 26

a body of air with horizontally uniform levels of temperature, humidity, and pressure. They are distinguished by the latitudinal location and type of surface of their regions.

Question 27

source region

Answer 27

an extensive region of the earth's surface where large masses of air having uniform temperature and humidity conditions characteristic of the region originate.

Question 28

stability

Answer 28

Stable air resists uplifting and mixing. Often air temperature increases with altitude (precipitation is unlikely to occur) Unstable air, convectional mixing and uplifting of air readily occur. Air temp decreases with altitude (uplift will cause cooling and this can result in precipitation)

Question 29

dewpoint temperature

Answer 29

The dewpoint temperature is the temperature at which the air can no longer "hold" all of the water vapor which is mixed with it, and some of the water vapor must condense into liquid water. The dew point is always lower than (or equal to) the air temperature.

Question 30

Wind rose

Answer 30

A diagram showing the relative frequency of wind directions at a place.

Question 31

Pressure gradient force

Answer 31

The pressure-gradient force is the force which results when there is a difference in pressure across a surface.Winds move from high to low pressure, across isobars. (The deflective force - coriolis force - offsets the pressure gradient force. Because the wind is deflected it now flows parallel to isobars = geostrophic wind.)

Question 32

Anemometer

Answer 32

An anemometer is a device used for measuring wind speed.

Question 33

Coriolis effect

Answer 33

The effect is driven by the force of earth rotation creating a force deflecting moving objects like, winds, tides and ocean currents, to their right in northern hemisphere and to their left in southern hemisphere. (noted that the coriolis force offsets the pressure gradient force)

Question 34

Gradient wind

Answer 34

The gradient wind is a balance of the Pressure Gradient Force, centrifugal and Coriolis. A geostrophic wind becomes a gradient wind when the wind begins flowing through curved height contours. The curving motion introduces a centrifugal (outward fleeing) force.

Question 35

Geostrophic wind

Answer 35

Geostrophic winds come about because pressure gradient force and Coriolis force come into balance after the air begins to move. A geostrophic wind flows parallel to the isobars.

Question 36

Barometer

Answer 36

instrument measuring atmospheric pressure, used in forecasting the weather and determining altitude

Question 37

Friction force

Answer 37

Friction acts at the surface, the effect of friction decrease with altitude. Also, winds at the surface aren’t as strong as those at higher altitudes. Frictional force reduces the wind speed nearer the surface. Frictional force reduces the Coriolis effect. Friction changes the direction of the geostrophic wind. As a result wind flow across the isobars.

Question 38

Cyclonic flow

Answer 38

When the wind swirls anti-clockwise in the northern hemisphere or clockwise in the southern hemisphere

Question 39

Anticyclonic flow

Answer 39

When the wind swirls clockwise in the northern hemisphere or anti-clockwise in the southern hemisphere

Question 40

Ocean heat transport

Answer 40

Driven mostly by wind blowing over the surface. However, currents move slowly. Lag behind wind speed so often called drifts

Question 41

Upwelling

Answer 41

When winds cause surface waters to diverge from a region resulting in the upwelling of colder nutrient water producing cooler temperatures along the coast.

Question 42

Anabatic wind

Answer 42

a warm wind which blows up a steep slope or mountainside, driven by heating of the slope through insolation

Question 43

Thermohaline circulation

Answer 43

The movement of seawater in a pattern of flow dependent on variations in temperature, which give rise to changes in salt content and hence in density. Thermohaline convection loop. Warm surface waters flow into the North Atlantic, cool and sink to the deep Atlantic Basin

Question 44

Trade winds

Answer 44

The trade winds are the prevailing pattern of easterly surface winds found in the tropics, within the lower portion of the Earth's atmosphere, in the lower section of the troposphere near the Earth's equator. The trade winds blow predominantly from the northeast in the Northern Hemisphere and from the southeast in the Southern Hemisphere, strengthening during the winter and when the Arctic oscillation is in its warm phase

Question 45

Westerlies

Answer 45

the belt of prevailing westerly winds in medium latitudes in the southern hemisphere

Question 46

Hadley Cell

Answer 46

a large-scale atmospheric convection cell in which air rises in medium latitudes, typically about 30 degrees north or south

Question 47

Inter Tropical Convergence Zone (ITCZ)

Answer 47

a belt of low pressure which circles the Earth generally near the equator where the trade winds of the Northern and Southern hemispheres come together. Where warm humid air ascends. The ascending edge of Hadley Cells.

Question 48

Doldrum(s)

Answer 48

The equatorial band where there is atmospheric instability (sudden changes in weather) due to rising humid air. As a result, winds are calm. Correlates with the ITCZ.

Question 49

Horse Latitude(s)

Answer 49

Found at latitudes 30 Degrees North and South (between trade winds and westerlies), known for calm air, less precipitation: due to subtropical highs (gyres) found at these latitudes.

Question 50

Polar easterlies

Answer 50

The polar easterlies are the dry, cold prevailing winds that blow from the high-pressure areas of the polar highs at the north and south poles towards low-pressure areas within the Westerlies at high latitudes.

Question 51

Sea breeze cell

Answer 51

The sea breeze is a strong thermally- direct circulation cell that occurs in the day time.

Question 52

Valley wind

Answer 52

Similar to the land/sea breeze in that it results from differential heating. In the day, heating of the mountains is more intense and that results in air coming up from the valley (valley wind)

Question 53

Subtropical high pressure belt

Answer 53

is a significant belt of atmospheric high pressure situated around the latitudes of 30°N in the Northern Hemisphere and 30°S in the Southern Hemisphere.

Question 54

Slope winds

Answer 54

Mountain and Valley winds Day - upslope (mountain wind) Night - downslope (valley wind)

Question 55

Jet streams

Answer 55

A narrow variable band of very strong predominantly westerly air currents encircling the globe several miles above the earth. There are typically two or three jet streams in each of the northern and southern hemispheres.

Question 56

Rossby waves

Answer 56

Develop in the upper-air westerlies, bringing cold, polar air equatorward and warmer air poleward.

Question 57

Convergence

Answer 57

Where airflows or ocean currents meet, characteristically marked by upwelling (of air) or downwelling (of water).

Question 58

Katabatic wind

Answer 58

Cold flow of air travelling downward or down a slope (gravity driven). In Antarctica often 14-30 m/s.

Question 59

El Niño

Answer 59

An irregularly occurring and complex series of climatic changes affecting the equatorial Pacific region and beyond every few years, characterized by the appearance of unusually warm, nutrient-poor water off northern Peru and Ecuador, typically in late December. The effects of El Niño include reversal of wind patterns across the Pacific, drought in Australasia, and unseasonal heavy rain in South America.

Question 60

La Niña

Answer 60

La Niña is the positive phase of the El Niño Southern Oscillation and is associated with cooler than average sea surface temperatures in the central and eastern tropical Pacific Ocean.

Question 61

Sea Surface Temperature Anomalies

Answer 61

simply transient events, not part of specific patterns or trends. Eg; El Nino is an SST anomaly (abnormally warm temps appearing off Peru's coastline)

Question 62

Southern Oscillation Index

Answer 62

Air pressure difference between Tahiti and Darwin (weather stations)

Question 63

El Nino- Southern Oscillation (ENSO)

Answer 63

irregularly periodical variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean, affecting much of the tropics and subtropics. The warming phase is known as El Nino and the cooling phase as El Nina

Question 64

Teleconnections

Answer 64

A casual connection between meteorological or other environmental phenomena which occur a long distance apart

Question 65

Walker circulation

Answer 65

The Walker circulation, also known as the Walker cell, is a conceptual model of the air flow in the tropics in the lower atmosphere (troposphere).

Question 66

Thermocline

Answer 66

An abrupt temperature gradient in a body of water such as a lake, marked by a layer above and below which the water is at different temperatures.

Question 67

adiabatic cooling

Answer 67

Adiabatic cooling is the process of reducing heat through a change in air pressure caused by volume expansion. In data centers and other facilities, adiabatic processes have enabled free cooling methods, which use freely available natural phenomena to regulate temperature

Question 68

Condensation

Answer 68

water which collects as droplets on a cold surface when humid air is in contact with it.

Question 69

orographic lifting

Answer 69

Air rising over mountain. Change in temperature (cooling) alters the relative humidity. Saturation occurs. Clouds forms and possibly precipitation. Intercepting slope = windward slope (wetter). p Leeward slope - drier (rainshadow)

Question 70

convectional precipitation

Answer 70

Convectional Rainfall, the sun heats the ground and warm air rises. As the air rises it cools and water vapour condenses to form clouds.

Question 71

tropical cyclone

Answer 71

Develop over warm ocean surfaces (≥28 degrees celsius) between 8 and 15 degrees latitude, migrate westward and curve toward the poles. Characteristics; central ‘eye’(clear skies and calm winds) Air descends from high altitudes, warming. Wind speeds are highest at the ‘eye wall’ Winds spiral outward creating high wind speeds. Storm gains energy from the release of latent heat. Dies when removed from water, latitude belt and approaching land (with friction)

Question 72

hurricane

Answer 72

The term for a tropical cyclone in the western hemisphere.

Question 73

Winter monsoon

Answer 73

In January high pressure over the land produces dry winds.Air is flowing towards the ITCZ.

Question 74

typhoon

Answer 74

The term for a tropical cyclone in western pacific and Asia

Question 75

Summer monsoon

Answer 75

In July the position of the ITCZ moves North. Low pressure over the land causes winds to flow off the ocean. This brings heavy rainfall.

Question 76

tropical cyclone tracks

Answer 76

The positions of where cyclones were and their future positions based on strength of high- and low- pressure systems.

Question 77

Saffir-Simpson scale

Answer 77

It measures tropical cyclone intensity. Categories 1 to 5 (5 is most devastating) Measured by central pressure, storm surge and mean wind speed.

Question 78

Ice Ages

Answer 78

A glacial episode during a past geological period

Question 79

Interglacials

Answer 79

An interglacial period (or alternatively interglacial) is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age. The current Holocene interglacial began at the end of the Pleistocene, about 11,700 years ago

Question 80

climate proxies

Answer 80

Proxy data is data that paleoclimatologists gather from natural recorders of climate variability, e.g., tree rings, ice cores, fossil pollen, ocean sediments, coral and historical data.

Question 81

Little Ice Age

Answer 81

The Little Ice Age is a period between about 1300 and 1870 during which Europe and North America were subjected to much colder winters than during the 20th century. The period can be divided in two phases, the first beginning around 1300 and continuing until the late 1400s.

Question 82

Sunspots

Answer 82

A spot or patch that appears from time to time on the sun's surface, appearing dark by contrast with its surroundings

Question 83

dendroclimatology

Answer 83

Tree limb or tree-ring dating, is the scientific method of dating based on the analysis of patterns of tree rings, also known as growth rings.