Geosystems Chapter 4: Global Temperatures

What are greenhouse gases?

They absorb infrared waves as they reradiate from Earth’s surface and try to leave the atmosphere

What are the four things that impact global temperatures?

Latitude, Altitude and Elevation, Cloud cover, and Land-water heating differences

Does temperature decrease with an increase or decrease of altitude?

Increase of altitude

Air density decreases with an increase or decrease of altitude?

Increasing altitude

Thin air absorbs?

Less heat

True OR False: Do clouds impact temperature?

True

Low thick clouds do what?

Block light and cause cooling in temperature

High, ice-crystal clouds do what?

Allows light to reach the surface and warms the temperature

What are some characteristics of an Urban Heat Island?

• Conduct more energy (metal,glass, asphalt, concrete)

• Have lows albedos so they absorb heat

• Their homes, vehicles, and factories generate heat

What are Urban Heat Islands?

Places that have higher temperatures then their surroundings

What is an Urban Canyon?

Buildings block winds, insolation reflected on urban surfaces

What is an Urban Desert Effect?

Lower evaporation and plant transpiration is reduced

Land-Water Heating Differences

Continental: Temperature conditions are more extreme (land warms and cools rapidly)

• Less evaporation

• Surface is opaque

• Land has a lower specific heat

• Land has no mixing between layer

Marine: Temperature conditions more moderate (water warms and cools slowly)

• More evaporation

• Surface is transparent

• Water has a higher specific heat

• Water has mobility and mizes in vast ocean current

What is specific heat?

The heat required to raise the temperature of the unit mass (usually one degree)

Higher pressure =

More molecules

Lower pressure =

Less molecules

Air pressure will always move…

High to low pressure

What is air pressure?

Force per unit area exerted against a surface by the weigh of the air above it

Wind is causes by a change in…

Air pressure

What is a pressure gradient force?

Air flows from high pressure to low pressure

What are Isobars?

Are equal pressure lines that help indicate pressure gradients

Closer isobars show..

A higher the pressure gradient and stronger wind speeds

What is a Coriolis Force?

Deflects moving objects due to Earth’s rotation

Northern Hemisphere~ To the right

Southern Hemisphere~ To the left

High pressure does what to air..

Air descends and diverges

Low pressure does what to air?

Air ascends and converges

The pressure gradient force acting by itself on a nonrotating Earth causes..

winds to move form high to low pressure across isobars

Pressure Gradient Force+Coriolis Force=

Geostrophic Wind

Earth’s rotation adds the Coriolis forces, which

gives a “twist” to air movements, so high-pressure and low-pressure areas develop a rotary motion

High pressure air spirals intro

low pressure systems

Pressure Gradient Force + Coriolis Force + Friction =

Surface Winds

Friction adds a countering force to..

Coriolis, producing winds that spiral out of high areas into low areas

Intertropical Convergence Zone (ITCZ)

• Lies along the equator, a trough of low pressure and light or calm winds

• Has high precipitation year-round

At the equator there is the..

Equatorial Low Pressure Trough

• ITCZ

• Trade Winds

• High Precipitation

Hadley cells are

large atmospheric circulation patterns move energy and air from the tropics to the subtropics.

30 degrees North and 30 degrees South are

high pressure areas (subtropical high-pressure cells)

• Are dry and hot

• Westerlies

• Bermuda High

• Pacific High

Sub-Polar Low Pressure Cells are areas that are

• Cool and moist

• Aleutian low

• Icelandic low

• Polar front

Sub-Polar High-Pressure Cells areas are

• Frigid and dry

• Descend and diverges

• Polar easterlies

What are jet streams?

High-altitude river of high-speed air

• Caused by Earth’s rotation and atmospheric heating

Local and Regional Breezes are affected by..

The time of day (higher and lower temperatures)

Mountain and Valley Breezes are affected by…

The time of day (warmer and cooler air)

Surface currents are caused by..

Surface Winds

What is thermohaline circulation?

Deep currents caused by density differences in temperature and salinity

What are the two different types of ocean currents?

Surface currents and thermohaline circulation

What is an el niño southern oscillation?

A natural climate pattern in the Pacific Ocean where the sea surface temperatures fluctuate between warm phases (El Niño) and cool phases (La Niña)