Exam II (copy)

Actual Evapotranspiration

the amount of water annually transpired by plants and evaporated from a landscape, usually measured in millimeters

Pressure Gradient Force

Drives air from areas of higher barometric pressure to areas of lower barometric pressure, causing winds.

Coriolis Force

The apparent force, resulting from the rotation of the Earth, that deflects air or water movement.

Vapor Pressure

a measure of the force exerted by a gas above a liquid

Dew Point

the temperature at which the water vapor in the air becomes saturated and condensation begins

Relative Humidity

The amount of water vapor in the air at any given time is usually less than that required to saturate the air. Expressed as a percentage.

Evapotranspiration

The combined amount of evaporation and transpiration

Potential Evapotranspiration

the amount of evaporation that would occur if a sufficient water source were available

Condensation Nuclei

Microscopic particles on which water vapor condenses to form cloud droplets.

Radiation Fog

created when air near the surface cools by heat loss (radiation) at night

Advection Fog

a fog formed when warm, moist air is blown over a cool surface

Stratus Cloud

a gray cloud that has a flat, uniform base and that commonly forms at very low altitudes

Cumulus Cloud

A puffy white cloud with a flat bottom that forms at a low or medium elevation

Cirrus Cloud

Wispy, feathery clouds made of ice crystals that form at high levels.

Coalescence Process

Small cloud droplets collide to increase their size, overcome air resistance and fall to earth

Sensible Heat

the heat we can feel and measure with a thermometer

Latent Heat

heat stored or released when a substance changes state

Sublimation

solid to gas

Deposition

gas to solid

Vaporization

liquid to gas

Condensation

gas to liquid

Calorie

Amount of energy needed to raise temperature 1 gram of water 1 degree C

Adiabatic Principle

a gas cools as it expands and warms as it is compressed

Specific Humidity

The amount of water vapor in the air at a given time and place; expressed as the number of grams of water vapor per kilogram of air.

Lifting Condensation Level

The altitude at which condensation begins (the temperature of the rising air parcel reaches the dew point temperature)

Dry Adiabatic Lapse Rate (DALR)

The rate of temperature decrease for a rising parcel of dry air decreases as the parcel is lifted in the atmosphere. ~1°C/100m

Saturated Adiabatic Lapse Rate (SALR)

The rate of temperature decrease for a rising parcel of saturated air. Ranges from ~4 to 10°C/100m, depending on temperature.

Environmental Lapse Rate

the rate of temperature decrease with increasing height in the troposphere. ~6.5°C/100m

Air Mass

A huge body of air that has similar temperature, humidity, and air pressure at any given height

Source Region

area over which an air mass forms

Front

a surface of contact between two unlike airmasses

Orographic Precipitation

precipitation that develops when warm, moist air cools and condenses as it rises against mountains

Convectional Precipitation

The formation of precipitation due to surface heating of the air at the ground surface

Cold Front

A front where cold air moves in under a warm air mass. Brings dramatic temperature changes and can create severe weather.

Warm Front

a front where warm air moves over cold air and brings drizzly rain and then are followed by warm and clear weather

Occulted Front

The area where a cold front begins to overtake a warm front, thus lifting warm surface air aloft. Brings strong wind and precipitation

Stationary Front

A boundary between air masses that don't move possibly causing rain for several days

Rain Shadow Effect

Precipitation falls on the windward side of a mountain range, resulting in lush vegetation & a warm, moist climate on one side, but a desert area on the leeward side.

Tornado

A rapidly whirling, funnel-shaped cloud that reaches down to touch Earth's surface. In the northern hemisphere, they primarily rotate counterclockwise

Squall

a line of moving thunderstorms

tropical depression

a region of low pressure with counter-clockwise wind rotation that develops into a hurricane or tropical storm

collision-coalescence process

formation of precipitation, where tiny droplets accumulate, fall, and collide with other small droplets until rain drops form and fall.

Evaporation & Condensation

What are the two conditions required for precipitation to occur?

Average Environmental Lapse Rate

6.5°C/km

Convergence Zone

an area of severe storms where the frigid waters circulating around the Antarctic meet the warmer waters of the Atlantic, Pacific, and Indian oceans

frontal lifting

if warm and cool air collide, the warm air will be forced up

Orographic Lifting

cloud formation that occurs when warm moist air is forced to rise up the side of a mountain

Cyclone

center for low atmospheric pressure. Air spirals inward and upward. Associated with warm fronts

Anticyclone

center for high atmospheric pressure. Air spirals outward and downward. Associated with cold fronts

Milankovitch cycles

Changes in the shape earth's orbit and tilt that cause glacial periods and interglacial periods.

paleoclimate

a climate prevalent at a particular time in the geological past.

interglacial period

A period of warmer temperatures between two ice ages.

glacial period

a period of ice advance associated with falling temperatures

Paleocene maximum

a time of rapid global warming in both marine and continental realms

Holocene Maximum

climate warming reached a peak at 5000 to 6000 years ago

hot house climate

A generally warm climate with little permanent ice like that in today's icecaps. They typically last hundreds of millions of years and have been the norm throughout Earth's history.

ice-house climate

Also known as glacial climates, relatively brief periods of colder temperatures on Earth, generally lasting only tens of millions of years having large areas of permanent (year-round) ice.

glaciation

a period of global cooling during which continental ice sheets and mountain glaciers expand

Younger Dryas

a stadial, or colder stage, between roughly 13,000 and 11,500 ya. The climate became colder and drier but did not return to full glacial conditions in higher latitudes

weather

The condition of Earth's atmosphere at a particular time and place.

climate

Overall weather in an area over a long period of time

wave cyclone

An extratropical cyclone that forms and moves along a front. The circulation of winds about the cyclone tends to produce a wavelike deformation on the front.

IPCC

Intergovernmental Panel on Climate Change, panel of scientists and researchers has been one of the main bodies in environmental control and standards in the international community

primary succession

succession that occurs in an area in which no trace of a previous community is present

secondary succession

Succession following a disturbance that destroys a community without destroying the soil

tolerance limits

each environmental factor has both minimum and maximum levels beyond which a particular species cannot survive or is unable to reproduce

ecotone

The transition from one type of habitat or ecosystem to another, such as the transition from a forest to a grassland.

The Atmosphere

the largest pool of nitrogen

Ammonification

decomposers convert organic waste into ammonia

Cloud

a collection of small water droplets or ice crystals suspended in the air, which forms when the air is cooled and condensation occurs

satelite altimetry

measures time taken for a radar to travel from the satellite to the sea and back. most accurate way to measure sea level

Phenology

the study of cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life.

eccentricity

change in the elliptical shape of the earth's orbit around the sun

obliquity

change in the tilt of earth's axis

precession

the gyroscopic wobble of the axis relative to fixed stars

20km

the thickness of the biosphere

net photosynthesis

difference between the rate of carbon uptake in photosynthesis and carbon loss in respiration

Net Primary Productivity (NPP)

The energy captured by producers in an ecosystem minus the energy producers respire

trophic level

Each step in a food chain or food web

species richness

the number of species per unit area

species abundance

number of individual species per unit area

species diversity

number of different species in a particular area weighted by some measure of abundance

how many species have been described on Earth?

about 2 million

what is the estimated number of species on Earth?

8.7 million

about how many new species are found every year?

around 10,000

what taxonomic group comprises the majority of known species?

insects

spacial variation

biodiversity within a given biogeographic range such as a specific ecosystem or community.

temporal variation

the frequency and magnitude of fluctuations in ecosystem structure

what are the abiotic explanations for latitudinal trends in biodiversity?

the tropics are a very stable ecosystem

what are the biotic explanations for latitudinal trends in biodiversity?

the tropics are home to heterogeneous habitats, which are associated with species richness.

cosmopolitan species

highly adaptable species that can be found in environments all over the world.

endemic species

native species unique to a certain small area.

evolution

change in the characteristics of a population that is heritable, or capable of being passed on from one generation to the next

natural selection

a process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.

migratoin

exchange of genes between populations

genetic drift

a change in the gene pool of a population due to chance

four causes of evolution

natural selection, mutation, migration, genetic drift

allopatric speciation

the formation of new species that occurs when populations are geographically separated

vicariance

the process by which the geographical range of a species is isolated by a historical event

jump dispersal

the dispersal of a species across a geographic range not previously occupied by the species.