Earth Science Chapter 14: Climate
Study review sheet!!!
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Study the dewpoint sheet and make sure you know how to solve missing variables
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Most recent ice age
10,000 years ago
The shape of Earth's elliptical orbit appears to change, becoming more elliptical, then more circular, over the course of a _____ year cycle
100,000
The angle of the tilt varies from a minimum of ___ to a maximum of _____ every _____ years
22.1º 24.5º 41,000
Angle of the axis tilt now
23.5º
What does this circulation that is driven by a semipermenant high pressure system create?
A cool, dry climate along much of the northwestern coast of South America
Example of the above theory?
A decrease in the angle of the tilted axis might cause a decrease in the temperature difference between winter and summer
Maunder minimum
A period of very low sunspot activity that occurred between 1645 and 1716 and closely corresponded with a cold climatic episode called the "Little Ice Age"
Most meteorological data is gathered where and why?
Airporrts, which cannot operate without up-to-date, accurate weather info
What is the result of glaciers moving this way in the US?
Aparent in the Great Lakes and the Finger Lakes of central New York, which were scoured out as the glaciers retreated
Tropics
Area if earth that receives the most solar radiation, is generally warm year-round, and extends between 23.5º south and 23.5º north of the equator
Temperate zones
Areas of earth that etend between 23.5ª and 66.5º north and south of the equator and have moderate temperatures
Polar zones
Areas of earth where solar radiation strikes at a low angle, resulting in temperatures that are nearly always cold; extend from 66.5º north and south of the equator to the poles
2 subtypes of dry climates
Arid regions or deserts Semi-arid regions or deserts
One of the most significant influences on Earth's climate
Atmosphere
How was the US's climate 50,000 years ago?
Average temps were several degrees cooler The jet stream was probably farther south
Climate
Average weather of a particular area over a long period of time; includes annual variations in temperature and precipitation, which are influenced by latitude, closeness of lakes and oceans, typography, wind patterns, and air masses.
Continental climate
Battlegrouds for clashing tropical and polar air masses Thus, these zones experience rapid and sometimes violent changes in weather Both summer and winter temperatures can be extreme because the influence of polar air masses is strong in winter, while warm tropical air dominates in summer Warm, moist air causes summers to be generally wetter than winters, especially in latitudes that are close to the tropics
Why does the amount of solar radtion received by any one place vary?
Because earth is tilted on its axis, and this affects how suns rays strike earths surface.
Why must we closely examine those activities and work to reduce their environmental impact?
Because global warming appears to be linked to human activities that cause pollution or widespread deforestation
The additional snow in latitudes near the poles would not melt in the summer why?
Because temperatures would be cooler than average. This could result in expanded glacial coverage
Why is the island's average weather conditions, or climate, have maritime tropical characteristics
Because this island is located in an area where maritime tropical (mT) air masses dominate the weather
What did Europe experience at this time?
Bitterly cold winters and below normal temperatures year round; Londoners could ice skate in June
Volcanic dust can remain suspended in the atmosphere for several years, doing what?
Blocking incoming solar radiation and thus lowering global temperatures
How can individuals combat global warming?
By conseving energy, which in tern reduces the consumption of fossil fuels
While normals offer valuable information, they must be used with?
Caution
What else are climatic changes triggered by?
Changes in Earth's axis and orbit
Why do climatic normals based on airport data differ quite a lot from actual weather conditions in nearby cities?
Changes in elevation and other factors like proximity to large bodies of water that can cause climates to vary.
Air masses affect what?
Climate
Reasons for weather differing across the nation
Climatic variations including: Latitude Topography Closeness of lakes and oceans Vailability of moisture Global wind patterns Ocean currents Air masses
Tropical climates
Constant high temperatures 600 cm of rain annually Heat 🔥 + rain ☔️ = tropical rain forests, which have some of the most dramatic vegetation on Earth Always under the influence of maritime tropical air
Some scientists theorize that periods of high volcanic activity causes what?
Cool climatic periods
Are mountain climates cooler or warmer than those at sea level
Cooler
Dry climates
Cover about 30% of Earth's land areas Largest climatic zone Most of the world's deserts (Sahara, Gobi, Australian) are dry Continental tropical air dominates Low precipitation Scarce vegetation Near the tropics Intense amounts of solar radiation means high rates of evaporation nd few clouds Moisture deficit
Temperaturesin the lower atmosphere generally ___ with altitude
Decrease
Weather conditions on any given day might...
Differ widely from normals
Koeppen classification system
Divides climates into 5 basic types, based on the mean monthly values of temperature and precipitation and types of vegetation
Marine coast climates
Dominated by the constant inland flow of air off the ocean, which creates mild winters and cool summers with abundant precipitation throughout the year In San Francisco, CA
Deforestation and CO2
During photosynthesis, vegetation removes carbon dioxide from the atmosphere. When the trees are cut down, rate of photosynthesis are reduced and more carbon dioxide remains in the atmosphere. Many scientists hypothesize that deforestation intensifies global warming trends
What happens when the orbit elongates?
Earth passes closer to the sun, and temperatures become warmer than normal
What happens when the orbit becomes more circular?
Earthis farther fromt he Sun and temperaturers dip below average
The end of El Nino
Eventually, the South Pacific high pressure system becomes reestablished and El Nino weakens, but not bfore it causes the climatic effects like droughts or floods. The warm water moves back across the Pacific Ocean, and conditions along the South AMerican coast cool off
What did English astronomer E. W. Maunder provide in 1893?
Evidence of a possible link between solar activity and Earth's climate
What is the end result?
Extensive property damage and untold human suffering
What does this positive effect result in?
Fewer hurricanes in that reggion for the duration of El Nino.
Polar climate variation
Found at high elevtions Includes parts of the Andes mountains of South America near the equator. The intense solar radiation found such equatorial regions is offset by the decrease in temperature that occurs with altitude
The existence of sunsport cycles lasting about 11 years had been recognized since the days of?
Galileo
What does the sudden presence of this warm water heat do?
Heats up the air near the surface of the water
Climatic changes occurred long before...?
Humans came onto the scene
3 mild climate subtypes
Humid subtropical climates Marine west coast climates Mediterranean climates
Interglacial intervals
Ice ages alternate with warm periods
Mediterranean climates
In Italy and parts of Spain Influenceed by the Mediterranean Sea Summers are warm bc of the lack of cool ocean currents in the Mediterranean Sea in relatively warm water temperatures
Meanwhile, the trade winds and ocean currents move westward across the tropics, keeping warm water where?
In the western pacific
This is especially true where?
In tropical regions, where El Nino's effects are most pronounced
Prime source of atmospheric CO2
Industriall emissions Car exhust Any process that involves the burning of a fossil fuel and results in the release of carbon dioxide and other gases into the atmosphere
Humid subtropical climates
Influenced by the subtropical high pressure systems that are normally found over oceans in the summer In the southeastern US Warm, muggy weather prevails during the warmer months and dry, cool conditions predominate during the winter
What do scientists theorize?
It's posible to increase or decrease the amount of atmospheric greenhouse gases, particularly CO2
For this reason, deserts are common on the _____ sides of mountains
Leeward
Microclimate
Localized climate that differs from the surrounding regional climate
Solar radiation strikes the polar zones at a ____angle
Low
The data used to describe an area's climate are compiled from?
Meteorological records
Steppes
More humid than deserts, generally separate arid regions from bordering wet climates
Climates often differ on either side of a _____
Mountain
What affects the climate?
Natural cycles of Earth and the Sun
Greenhouse effect
Natural heating of earths surface by certain atmospheric gases, which helps keep earth warm enough to sustain life.
A good way that Koeppen discovered to distinguish among different climatic zones and example
Natural vegetation. Palm trees don't grow in polar regions
Can either viewpoint be proven or disproven conclusively?
No
During the average human lifetime, do climates appear to change signficantly?
No
In the Southeast Pacific Ocean, atmospheric and coean currents allong the coast of South America normally move____, transporting cold water from the Antarctic region
North
Solar radiation that is not not what does what?
Not reflected by clouds passes freely through the atmosphere. It's then absorbed by Earth's surfce and released as long wavelength radiation. This radiation is absorbed by atmospheric gases then reradiate the stored energy, so that Eart receives energy from 2 sources: the Sun and atmosphere
Normals: what they are and aren't intended to do?
Not: to describe usual weather conditions Are: simply the average values over a long period of time
Leeward side
On the opposite side, the air is dry and warms as it descends
Increase in the greenhouse effect might cause what?
Our planet to be hot, like Venus, which, because of its thick atmosphere, has surface temperatures of 470ºC.
The properties of air masses are also dependent on whether they formed?
Over land or water
Ice ages
Period of extensive glacial coverage, producing long-term climatic changes
What happens if this trned continues?
Poar ice caps might melt Sea level might rise and flood coastal cities Deserts could spread into fertile regions The frequency and severity of storms would increase
What is this theory supported by?
Records over the past century because several large eruptions have been followed by below normal global temperatures. For instance, the ash released during the 1991 eruption of Mt. Pinatuba in the Philippines rsulted in slightly cooler temperatures around the world the following year
Global warming
Rise in global temperatures, which may be due to increases in atmospheric carbon dioxide from deforestation and burning of fossil fuels a phenomenon related to the greenhouse effect.
Air does what with a mountain?
Rises up one side of a mountain as a result of orographic lifting. The rising air cools, condenses, and drops its moisture.
Wladimir Koeppen
Russian-born German climatologist
What allows the jet stream to shift farther south
Sharp temperature differences in the upper air
Generally, volcanic eruptions appear to have only what type of effects on climate?
Short term
Seasons
Short term period of climatic change caused by regular variations in temperature, hours of daylight, and weather patterns that are due to the tilt of earths axis as it revolves around the sun, causing different areas of earth to receive different amounts of solar radiation.
Water heats up and cools down more ______ than land
Slowly
Air masses have distinct regions of origin, caused primarily by differences in the amount of ______ ______
Solar radiation
Normals
Standard values for a location, including rainfall, wind speed, and temperatures, based on meteorological records compiled for at least 30 years
Convection currents do what?
Strengthen, and the normally cool and dry northwestern coast of South America becomes much warmer and wetter. The increased precipitation pumps large amounts of heat and moisture into the upper level atmosphere, where upper level winds transport the hot, moist air eastward across the tropics
What provides evidence of past climatic changes?
Studies of tree rings, ice-core samples, fossils, and radiocarbon samples
Climatology
Study of Earth's climate in order to understand and predict climate change, based on past and present variations in temperature, precipitaation, wind, and other weather variables
Currently, when do winters occur in the northern hemisphere and when do summers occur?
Summer=when Earth is farthest from the Sun Winter=when Earth is closest to the Sun
What do some scientists hypothesize about ice ages?
That changes in the angle of Earth's tilted axis could cause ice ages
What did Maunder find?
That from 1645 to 1716, sunspot activity was scare to nonexistent
What do studies indicate?
That increased solar activity coincides with warmer-than-normal climates, while periods of low solar activity, liketh Maunder minimum, coincid with cold climatic conditions
What did Koeppen later realize?
That quantitative values would make his system more objective and therefore more scientific. Thus, he revised his sytem to indicate the numerical values of temperature and precipitation
What does mounting evidence indicate?
That the warming trend is a result of increases in atmospheric carbon dioxide
What do scientists theorize about these changes in angle?
That these cause seasons to become more severe
Windward side
The climate on this side (where air rises, cools, condenses, and drops moisture) is usually wet and cool
What do large bodies of water affect?
The climates of coastal areas
In North America, glacier spread from where to where?
The east coast to the west coast and as far south as Indiana
What else can climatic changes be triggered by?
The immense quantities of dust released into the atmosphere during major volcanic eruptions
Increase in the amout of these gases would theoretically result in what?
The increase absorption of radiation
Some scientists hypothesize that these natural changes adequately explain what?
The increased temperatures
The smaller the difference between the difference and the dry bulb...
The more humidity and rain is likely
2 main causes of weather
The movement and interactions of air masses
Normals apply only to?
The specific place where the meteorological data were collected
One positive El Nino effect
The strong upper winds it produces keep tropical disturbances from increasing to hurricane-strength storms in the Atlantic Ocean
This high pressure system and its attendent trade winds weaken drastically, which allow what? Why does this happen
The warm water from the western Pacific to surge eastward toward the South American coast We don't know
What can climatic dta indicate?
The warmest and coldest temperatures ever recorded for a location.
What is responsible for dramatic climatic changes?
This hot, moist air in the upper atmosphere
During the summer in the northern hemisphere, the north pole is what?
Tilted toward the Sun, and this hemisphere experiences long hours of daylight and warm temperatures. At the same time, it is winter in the southern hemisphere. The south pole is tilted away from the Sun, and the southern hemisphere experiences long hours of darkness and cold temperatures. Throughout the year, the seasons are reversed in the north and south hemispheres
Polar climates
To the north of continental climates Coldest regions on Earth Constant cold:temperatures in the warmest month are below 10ºC Generally low precipitation bc cold air holds less moisture than warm air The amount of heat radiated by Earth's surface is too low to produce the strong convection currents needed to release heavy precipitation
Microclimate example
Top of a mountain, where it's colder with increasing elevation
Tropical wet and dry zones
Transition zones that border the rainy tropics north and south of the equator which have distinct dry winter seasons as a result of the occaisional influx of dry continental mair masses. Include savannas
Types of climates (5)
Tropical Dry Mild Continental Polar
Most scientists agree that global warming is occurring: true or false?
True
Ways to conserve energy
Turning off appliances and light when not in use Turning down thermostats int he winter Recycling
Heat islands
Urban area where climate is warmer than in the surrounding countryside due to factors like numerous concrete buildings and asphalt Greater changes in temperature with altitude, which sparks strong convection currents
These changes in Earth's climate were caused by what types of natural events?
Variations in solar activity, changes in Earth's tilt and orbit, and volcanic eruptions
El Niño
Warm ocean current that develops off the western coast of South America and can cause short term climatic changes worldwide
Continental climates 3 subtypes
Warm summer climate Cool summer climate Subarctic climate
Winters would be __ and _______, summers should be ________
Warmer and wetter Cooler
What does this cause?
Weather systems to take a more southerly track, bringing storms to California and the Gulf Coast, which are usually south of the storm tracks
What do they disgaree on?
What causes global warming
What is the amount of radiation Earth receives when its orbit elongates much higher than?
When its orbit is not circular
This type of info + comparisons between recent conditions and long term averages can be used by companies to decide what?
Where to locate new facilities and by people who have medical conditions that require them to live in certain climates
What happens when the axis tilts toward Vega?
Winter will occur in the northern hemisphere when Earth is farthest from the Sun and summer when it is closest to the Sun. This will cause warmer summers and colder winters than those we now experience
What does Earth do on iits axis?
Wobbles
Without the greenhouse effect, life as we know it... what would earth be like?
Wouldn't exist on Earth Like mars, cold and with a very thin atmosphere and surface temperatures that go below -90º C
Are climates in a constant state of change?
Yes
Have temperatures worldwide continuted to increase?
Yes
The effects of hot, moist upper air spread farther east, bringing what to what?
stormy weather to areas that are normally dry and drought conditions to areas that are normally wet
Avrage weather conditions in and near regions of air mass formation are fairly similar to?
those exhibited by the air masses themselves
Many coastal regions are _____________________________ than inland areas of similar latitude
warmer in the winter and cooler in the summer
Because of Earth's wobbling, the axis will do what?
will tilt toward another star, Vega, by about the year 14,000
