Geography 140
Introduction to Physical Geography

Lecture: Climates

I. Climate could be defined as the trends in typical weather:
A. Temperature of an area:
1. Its mean or average:
a. Annually
b. Monthly
c. Average monthly daytime highs and nighttime lows
2. Its typical degree of variation:
a. Range or standard deviation in annual averages
b. Range or standard deviation in monthly averages
c. Range or standard deviation in monthly highs and lows
3. When the highest and lowest monthly averages are experienced
B. Precipitation:
1. Types commonly experienced: rain, snow, sleet, hail
2. Averages
a. Annual receipt
b. Receipt by month
3. Typical variation
a. Extreme ranges annually and monthly
b. Standard deviations annually and monthly
4. When the highest and lowest monthly averages are experienced
5. Duration of drought
C. The balance between precipitation and evapotranspiration: Dry climates
can evaporate or transpire more water than they actually receive; wet
climates may run a surplus of precipitation over evapotranspiration;
surpluses and deficits may exist at different times of the year.

II. A number of climate classification systems are encountered in physical
geography. They might be based on annual and monthly averages of
temperature and precipitation or perhaps on the balance between
precipitation and potential evapotranspiration (itself based on
temperature).
A. C. Warren Thornthwaite developed a water budget approach, based on
potential evapotranspiration compared to water receipt. The result
was 32 climate types based on five major water budget provinces:
rainforest, forest, grassland, steppe, and desert. It's rather
cumbersome for my purposes here, but I wanted to mention it. You can
see the basic idea in this graph, which shows the monthly march of

potential evapotranspiration (POTET) as a green line and monthly
receipt of precipitation as a red line. A deficit is shaded.

B. Wladimir Köppen devised a system based on monthly temperature averages and
precipitation receipt, which he and his student, Rudolf Geiger put
together into a wonderful map of the world's climates, called the
Köppen-Geiger map, which you can view by clicking here.

1. His system has six main categories:
a. A: Tropical humid climates
b. B: Dry climates (arid and semiarid), in which POTET exceeds
precipitation
c. C: Temperate or subtropical mid-latitude climates
d. D: Mid-latitude climates with cold, snowy winters, in which the
warmest month must average at least 10° C, but the coldest
month must average less than -3° C.
e. E: Cold climates, in which no month averages above 10° C
f. H: Highland climates are the highly varied microclimates we see
on a mountain, including even polar-like climates at the top of
those mountains taller than timberline.
2. Then, he subdivides these six major categories into a series of
minor subcategories, which pretty neatly characterize the different
climate experiences around the world, so I'll orgration (POTET) as a red line and monthly receipt
of precipitation as bars. The bars are, helpfully, shaded green whenanize this lecture
loosely around Köppen.

III. Tropical climates (the A climates). All months have average temperatures
(day and night averaged together) above 18° C and annual
precipitation totals of at least 1,800 mm
A. Tropical Rainforest (sometimes called Equatorial Wet)
1. Classified Af. The f stands for German "feucht" ("foikht") or
moist.
2. This climate is warm all year round. There is less than 3° C
of temperature difference between the hottest and the coldest
monthly average! The day temperatures are around 32° C (upper
80s F) and the nighttime temperatures are around 22°C (very
pleasant room temperature). So it never gets terribly hot or cold.
3. There is no dry season: The driest month gets at least 6 cm of
rain.
4. This essentially seasonless climate is influenced by the ITCZ all
year round.
5. If you look at the map above, you'll see that the location of the
Af climate is right along the equator
a. The Amazon Basin of Brazil in South America
b. The Congo Basin in central Africa
c. The Indonesian Archipelago and the Malaysian Peninsula
B. Tropical Monsoon
1. Classified Am
2. This two season climate has a short but noticeable winter dry
season, but it rains so bloody hard during the summer that the area
is able to support tropical rainforest vegetation anyhow.
3. This climate is generally affected by the ITCZ but is far enough
away from the equator to be affected by the fringes of the
Subtropical High during the winter when the world pressure and wind
system moves out of a hemisphere, as seen in this spiffy animation:

4. When the monsoonal circulation of summer hits, though, it more than
makes up for its short summer POTET deficit: Some of the highest
precipitation totals in the world fall on these climates.
5. The places having this climate are not far from the equator and the
tropical rainforest climates (see map:
a. Sierra Leone and Liberia in western Africa north of the equator
b. The northwest coast of Brazil in South America
c. Southwesternmost India and Sri Lanka
C. Tropical Wet and Dry (sometimes called Tropical Wet-Dry or Tropical
Savanna).
1. It is classifed Aw (for winter dry season)
2. This is a two season climate.
3. During the summer, the ITCZ moves over it as the ITCZ moves higher
into a hemisphere, and this results in a rainy, warm summer. In
another variation, sometimes a mountainous east coastal location in
the tropics will be covered by the onshore Trade Winds during the
summer, similarly producing a rainy summer through orographic
uplift.
4. It is covered, instead, by the Subtropical High during the winter,
which gives it "Sahara Desert" summers: very dry, very hot (kind
of like the California summer, actually).
5. The dry season lasts so long and the summer rain does not
compensate for the winter drought, so this climate cannot support
tropical rainforest vegetation. Instead, it is covered with
tropical deciduous woodland or savanna (a mix of tall grass and
clumps of mid-size trees)
6. So, you'd expect to find it poleward of the tropical rainforest and
tropical monsoon climates, surrounding them, and you'd be right,
for example (see map):
a. Most of central Africa outside the Congo Basin, extending down
east Africa (which is too high to have a tropical rainforest
climate).
b. Most of Brazil south of the Amazon rainforest and north of it.
c. Most of Indochina: Vietnam, Cambodia, Thailand
d. Northernmost Australia

IV. Dry climates. These experience moisture stress most of the year.
A. BW climates: true deserts (from German "Wüste" or wasteland).
These are extremely dry and can support only desert scrub and, in some
cases, almost no vegetation at all.
1. BWh -- Tropical desert (from German "heiss" for hot). Like the A
climates, a BWh climate has an average annual temperature of at
least 18° C.
a. This desert is the one strongly affected by the Subtropical High
all year round. Imagine the California summer ... all year
round.
b. Tropical deserts not only are found around 30° N or S, they
also open out onto the west coasts of continents, where that
cold current is found. The cold current wrings out any moisture
that might have formed precipitation onshore.
c. Sometimes the part of the desert opening out on the west coast
will experience fog in summer, kind of the way Long Beach does.
If so, that narrow strip of coastal desert is further called
BWhn (from German "nebel" or fog).
d. With these characteristics, it is easy to predict where you'll
find these climates. Look at the map above:
i. The Sahara Desert system, which extends around 10-20° N
from the Sahara proper in North Africa, through the deserts
of the Middle East, clear into the Thar Desert of Pakistan
and northwest India. The mother of all desert systems.
ii. The Namib Desert of southwestern Africa, Namibia.
iii. The Great Sandy Desert of Australia, the Outback.
iv. The Atacama Desert of northern Chile and Peru: The driest
desert on Earth, by the way (it's gone as long as thirteen
YEARS without even trace precipitation!)
v. The Sonoran or Colorado Desert of northwestern Mexico
(including Baja) and the American extreme Southwest
(including Palm Springs): Californians call this the "Low
Desert" because of its low elevation.
2. BWk -- Temperate Desert or Mid-latitude Desert or Temperate Arid
(from German "kalt" for cold).
a. This climate is also extremely dry, unable to support more than
desert scrub vegetation.
b. Unlike the tropical desert, though, it can get awfully cold in
the winter. To be classified BWk, it has to average below
18° C, and some months are so cold as to see snow.
c. In some ways, this is even tougher on plants: They have to
adapt to extreme heat and dryness AND freezing cold, too.
d. These deserts form in rainshadows in the Prevailing Westerlies
belt, so you expect to find them on the leeward side of
mountain ranges, usually to their east or, sometimes, north (in
the Northern Hemisphere), as seen in the map.
i. The Gobi Desert of Mongolia and inner China, in the
rainshadow of the Tibetan Plateau.
ii. The Central Asian deserts in the rainshadow of the Zagros
Mountains of Iran.
iii. The Patagonian Desert of Argentina, in the rainshadow of
the Andes.
iv. The Basin and Range deserts of eastern California, Nevada,
and Utah, in the rainshadow of the Sierra Nevada.
v. The Mojave, in the rainshadow of California's Transverse
and Tehachapi ranges (what we call the "High Desert"
because it is at higher elevations).
3. BSh -- Tropical Semi-Arid or Tropical Steppe.
a. Like the Tropical Desert and the A climates, this one also has
an annual average temperature of at least 18° C.
b. It is a bit more humid than the true desert, so it supports a
somewhat denser scrub vegetation or some grass.
c. When it gets rain, it's in the summer, when the fringe of the
ITCZ might move far enough poleward to affect this area.
Winters are bone dry and hot, like the Sahara. The rainfall is
very unpredictable here. It's something of an axiom in
climatology that the drier a climate is the more unpredictable
its precipitation becomes. In good years here, the vegetation
gets almost lush: a lot of grass; in bad years, it is almost
bereft of anything but the occasional shrub and blade of grass.
d. This climate is a transition, then, from Tropical Wet and Dry
climate to Tropical Desert, and that's a clue to where to find
it. Examining the map above, you'll see BSh climates in:
i. Africa just south of the Sahara, in a great band known as
the Sahel (which has often been in the news with repeated
droughts and famine).
ii. Africa to the southwest, east of the Namib Desert: The
Kalahari Steppe.
iii. In Australia, fringing the desert of the interior.
iv. Most of northern Mexico.
4. BSk -- Temperate Semi-Arid or Mid-Latitude Semi-Arid or Temperate
Steppe.
a. Dry, but not as bone dry as temperate desert
b. Not as hot as tropical steppe, with average annual temperatures
under 18° C -- and, like temperate desert, it can get pretty
wickedly cold in the winter.
c. Like the tropical steppe climate, it can support a steppe
vegetation, a mix of short to medium grasses and shrubs in good
years and just the shrubs and a few short grasses in bad years.
d. Like the tropical steppe climate, it is a transition climate.
In this case, it forms a transition between temperate desert and
a variety of surrounding more humid climates (e.g.,
Mediterranean, humid subtropical, humid continental).
e. So, we find it on the perimeter of temperate desert:
i. Surrounding the Gobi Desert
ii. To the north of the Central Asian deserts, extending west
to the Ukraine ("steppe" is a Ukrainian word for the
associated vegetation, actually).
iii. Much of the Iranian highlands
iv. The Pampas area in Argentina, surrounding the Patagonian
Desert.
v. The American Great Plains east of the Rockies
vi. The northern Basin and Range: northern Nevada, southern
Idaho.

V. Mild winter mid-latitude climates. As a group, these very different
climates share two common temperature characteristics: Their coldest
month must average below 18° C but above -3° C; their hottest
month must average warmer than 10° C. Other than that, they really
differ from one another.
A. Cf climates are moist ("feucht) and mild: They have no dry season.
No month gets less than 3 cm of precipitation. There are two very
different versions of this basic type:
1. Cfa, "a" meaning hot summer, with the warmest month averaging above
22° C. These are called Humid Subtropical climates.
a. This climate receives precipitation in the winter from mid-
latitude wave cyclones as the Subpolar Low and the Westerlies
move closer to the equator in winter. This precipitation is
mostly in the form of rain, but sometimes in the form of snow.
b. During the summer, this climate receives precipitation as a
result of the movement poleward of the Subtropical High and its
breakup into concentrated, circular cells in the oceans. These
peaks of high pressure (e.g., the Bermudas High) generate
spiraling outflows of air. Off the east coasts of continents,
these winds flow over the warm currents in those locations
(e.g., the Gulf Stream), picking up beaucoup water vapor
through evaporation. This moisture-loaded air then hits the
east coasts of continents and convectional and orographic
processes create lots of summer thunderstorms: It rains a LOT
in this climate during the summer and, when it isn't raining,
it's really pretty sticky.
c. The responsible processes are a clue to the locations of this
climate. If you look at the map above, you can find Cfa
climates in subtropical latitudes, oh, about 30-40° N or S,
but on the EAST coasts of the landmasses. For example:
i. The American Southeast (think of New Orleans, Atlanta,
Houston, and Washington DC in the summer -- 'nuff said)
ii. Southeast China and southern Japan (Shanghai, Tokyo)
iii. Southern Brazil, Uruguay, and northeast Argentina
(Montevideo and Buenos Aires)
iv. Southeast Australia (Sydney, Brisbane)
2. Cfb -- "b" meaning mild summer: No summer month averages above
22° C. This is called the West Coast Marine climate (guess
where it's found). Like the Humid Subtropical climate, this one is
also moist all year round, with no month averaging below 3 cm.
a. This climate is affected by the Subpolar Low and the Westerlies
all year round: It never escapes the humidity and raininess
associated with these, though it is a bit weaker in the summer,
since the Subpolar Low shifts poleward, reconnects over land,
and weakens. The Westerlies flow, however, is always bringing
moisture ashore from the tepid remains of the warm drifts in
these latitudes.
i. The Japan or Kuroshio Current becomes the North Pacific
Drift, which, well, drifts eastward until it hits the
Pacific Northwest and then turns south toward California
(becoming relatively colder as it moves south, eventually
becoming our California Cold Current). Up around Sitka and
Seattle, though, it is still relatively tepid and so the
Westerlies flow brings water vapor evaporated from that
Drift onshore. So, now you understand Seattle's and
Vancouver's famously soggy summers.
ii. The same thing goes on in Northwest Europe: The Gulf
Stream becomes the North Atlantic Drift and the Subpolar
Low and Westerlies bring that moisture ashore, giving
London its famous pea-soup charm (they get REALLY excited
when there's an actual sunny day there!).
b. Well, discussing the mechanisms responsible for this climate,
I've inadvertantly spilled the beans about two of its major
locations: The Pacific Northwest (including British Columbia
and southeasternmost Alaska) and Northwest Europe (England,
Ireland ["the Emerald Isle," from all that water], northern
France, the Netherlands, northern Germany). There are a few
others:
i. Southern Chile at the southwest end of South America
ii. Tasmania and the southeasternmost corner of Australia and
New Zealand.
iii. The southeasternmost tip of southern Africa.
c. There are also a few places that are basically West Coast Marine
in character but have short, cool summers: Cfc. Like regular
old Cfb, these never average above 22° C, but they have
fewer than four months that manage to squeak averages above
10° C. These are found on the poleward fringes of the West
Coast Marine regime (southern Alaska, southern Scandinavia).
B. Cs climates, known as Mediterranean climates. Like any C climate,
these are warm climates, with no winter month averaging below -3°
C or above 18° C. Like all C climates, Mediterranean climates
have their warmest months averaging above 10° C.
1. That said, the BIG difference is these are summer-drought climates:
That's what the "s" stands for. These are essentially two season
subtropical climates, with the dry season in the summer, which is
QUITE unusual on Planet Earth. There are lots of two season
climates on Earth, but they tend to have their dry season in the
winter (e.g., the Am and Aw climates we met above).
2. What accounts for these climates is their position between the
Subtropical High and the Subpolar Low/Westerlies belts AND their
west coast locations (which brings those cold currents into play).
a. In the summer, the Subtropical High moves poleward, breaks into
concentrated circular centers over the oceans, and strengthens.
i. Sometimes Mediterranean climates are covered by the
subsiding air of these highs, which directly explains the
hot, dry, Sahara-like weather they get in the summers.
When this is going on, we often get gnarly smog situations,
because this subsidence is essentially a doozy of an
inversion layer, which can persist for days, even weeks,
while we sit hoist in our own petard of pollution.
ii. Most often, though, the oceanic highs are well out at sea,
generating airflow towards the landmasses. That air
spiraling out of, say, the Hawai'ian High then passes over
the cold California Current on its way to California, which
causes the humidity in the air to be lost out at sea (you
often see that moisture offshore as fog banks). Bingo:
dry air flow onshore and bone dry summers.
b. In the winter, the Subtropical High shifts equatorward and
weakens by reconnecting over land. This confers less protection
from storms. Meanwhile, the Subpolar Low shifts equatorward,
too, but it strengthens by concentrating into two oceanic pits
of low pressure and convergent air flow, generating lots of
winter storms. These, then, track over the land and their
precipitation affects Mediterranean climates (depending on the
path of the Polar Front Jet Stream). Voilà! -- rainy, cool winters.
3. These summer-dry subtropical climates are really pleasant amenity
climates and are actually quite rare. You find them from about,
oh, 30° N or S to, maybe, 40° N or S, always on the west
sides of landmasses:
a. The Mediterranean borderlands is the largest patch of this
climate, so it gets the honor of conferring its name on the
type: parts of Spain and Portugal, southernmost France (the
Riviera), Italy, the Balkan coast, parts of Turkey and Syria,
Lebanon, Israel, Morocco.
b. Most of California outside the deserts and highest mountains is
probably the next biggest patch.
c. Central Chile (around Santiago) in western South America
d. Southwesternmost Australia (around Perth) and another part on
the southwestern end of eastern Australia (around Melbourne) --
sorry I can't describe it more exactly -- look at the map above.
4. The Mediterranean climates are broken out into four subtypes that
are found in close proximity to one another, depending on local
topography (remember the normal lapse rate? It gets cooler up a
mountain, and that can affect summer high temperatures, which is
the basis of differentiating a, b, and c Mediterranean climates).
a. Csa climates are Hot Summer Mediterranean climates, with at
least one summer month averaging above 22° C. They tend to
get colder winters, too, experiencing the occasional frost. In
California, we find them more inland, e.g., the San Fernando
Valley and much of the Great Central Valley.
b. Csb climates are Warm Summer Mediterranean climates, which do
not have any month averaging above 22° C. In California, we
find it on hillsides from about Ventura north and, in interior
California, on the hillsides overlooking interior valleys (e.g.,
Sierra foothills above the Great Central Valley).
c. Csc climates are Short Summer Mediterranean occasionally found
at even higher locations.
d. Csbn climates are Warm Summer Mediterranean climates with fog
("nebel" in German). These are found on the coastal plain and
lower hillsides from about San Pedro and the Channel Islands
north to the Oregon border.
e. There is even a Dsb climate! This is not a true Mediterranean
subtropical climate, but it's a montane climate you find at
pretty high elevations in Mediterranean areas, which shares the
summer-drought pattern. These do get months averaging colder
than -3° C in the winter, receiving the bulk of their
precipitation as snow. This is what you find in the Sierra,
Cascades, and the San Bernardino and San Gabriel high country
below timberline.
C. Cw -- Temperate Wet and Dry climates are also found in the world (but
not in North America): These are Subtropical Winter-Drought climates
("w" is for winter dry season, just like we saw with the Aw climates
earlier).
1. These get at least ten times as much rain in the wettest summer
month than they do in the driest winter month.
2. They are mostly transitions from the Aw climate to the Cfa climate
wherever the two climates are found on the same landmass (which
knocks out North America). So you see a transition from the dry
winter of the Tropical Wet and Dry climate to the wet all year
Humid Subtropical climate, and a transition from the heat of the A
climates to the mildness of the C climates.
3. Looking at the map for such areas, we find them, predictably
enough, in:
a. South America in interior southern Brazil and Paraguay and
southeast Bolivia.
b. Central and southeasternmost China.
c. in southern and eastern Africa, especially around Tanzania and
Mozambique.

VI. D or Humid continental climates. The Df and Dw climates are sometimes
called Boreal climates. These are the classic snowy winter climates. As
a group, their coldest winter month must average below -3° C, but
their warmest month must average above 10° C (which turns out to be
the isotherm that limits tree growth: Poleward or upslope from this
isotherm, trees are no longer viable).
A. Df climates are moist ("feucht") all year, being affected by the
Subpolar Low and effectively receiving precipitation from it all year
round.
1. These climates are further subdivided into Dfa, Dfb, and Dfc
climates, just as we saw for the Cf and Cs climates (hot summer,
mild summer, and short summer). There is also a Dfd climate, too
(coldest month must average below -38° C!!!!) found only in a
small area of Siberia. I will treat the whole bunch as a group,
though. Do remember that they get progressively nastier as you
move north and east.
2. They are found poleward of the West Coast Marine (Cfb), Temperate
Semi-Arid (BSk), and Humid Subtropical (Cfa) climates. That means
you only find them in the Northern Hemisphere (no large enough
landmass in the right latitudes in the Southern Hemisphere)..
3. If you look at the map, you'll notice that these climates are not
found until really high latitudes on the west sides of landmasses
(60° N), but you find them at rather low latitudes (40 or
50° N) in the interior of the landmasses. That's because the
moderating influence of the North Pacific Drift and the North
Atlantic Drift keeps the temperatures from plunging down to the
extremes required for this family of climates. In the interiors,
however, you experience continentality, the low specific heat of
land (remember all that, how land heats up and cools down fast
compared to water?), so winter monthly average temperatures can
easily drop below -3° C.
4. So, you find the Df climates from central Alaska through most of
Canada and into the American upper Midwest and New England and from
central Scandinavia down through Northeastern Europe, European
Russia, and western Siberia.
B. Dw climates are basically the same thing, except they have a winter
dry season.
1. You find these only in the Old World, which is humongous enough
that most the moisture brought onshore by the Icelandic Low storms
and the Westerlies has been dropped on European Russia and western
Siberia, leaving nothing for points east.
2. So, you can see them on the map in North Korea, northeasternmost
China, and eastern Siberia.
C. Ds climates are D climates with a summer dry season. They are
basically highland climates in the Mediterranean complex of climates,
so I described them there, under Cs climates.

VII. E -- Way cold climates. No month averages above 10° C. Yeeeeee!
A. ET or Tundra climates (phone home?).
1. These get at least one month averaging above freezing, 0° C.
2. Their soils contain permanently frozen water: Permafrost.
3. They are extremely windy: The Polar Easterlies dominate the tundra.
4. But since they do average above freezing for a while in the summer,
this means they actually thaw out a bit in the summer. The top
layers of the frozen soil water thaw out and dribble down the
landscape, creating pools in any depression (home to countless
mosquito larvae, the Alaska Air Force!).
5. So they can actually support some plant growth.
a. No trees: They get knocked over by winds with the shallow root
structures necessary to live in the tundra. So, you're past
treeline here.
b. So, you have a mix of low-lying vegetation: shrubs, grasses,
sedges, ephemeral wildflowers, mosses, lichens.
6. You find tundra in really high latitude areas:
a. Along the northern and western coasts of North America north of
about 60° N.
b. Along the southern coasts of Greenland and the northern coast of
Iceland.
c. Along the northernmost coasts of Eurasia from northwestern
Norway to the Bering Strait.
d. There's also a small bit in northernmost Antarctica near the
southern tip of South America, Tierra del Fuego at that southern
tip of South America, and the Falkland/Malvinas Islands
(remember that absurd war between the then-Argentine military
dictatorship trying to keep power through patriotism and the
British trying to hang onto a little tundra real-estate, some
sheep, and ..... a spy station?).
7. There is also an alpine tundra climate, found on any mountain
taller than timberline. Basically, the normal lapse rate cools the
climate up a mountain so much that it gets cold enough to preclude
tree growth. Alpine tundra, like Arctic/Antarctic tundra, is also
very windy, which also prunes any ambitious plant. You can find
alpine tundra even right on the equator, in the Andes in Ecuador
and Mt. Kenya in East Africa.
B. EF -- Frozen climate. All months must average below freezing.
1. This enables the preservation of any snow from summer melt.
2. As a result, even small amounts of precipitation each year can
accumulate, year to year, building up glaciers.
3. There are two great continental glaciers in the world today, in
which the ice sheets can get thicker than 4 km!!! (2.5 miles of
ice!!!):
a. Antarctican ice sheets (which the map doesn't show):
i. East Antarctic ice sheet is on top of the Antarctican
continent
ii. West Antarctican ice sheet lies over water and is so thick
and heavy that its bottom has sagged 2 km below sea level
in its center.
iii. Seventy percent of the world's fresh water supply is in the
Antarctican ice.
b. Greenland ice sheet covers nearly all of the world's largest
island (this does show on the map).
4. During the different ice advances of the Pleistocene (the last one
peaked about 18,000 years ago), there were more such huge glaciers,
and about a third of the earth's land was covered in ice! Awesome!
a. The Laurentide ice sheet covered most of Canada and portions of
the northern US.
b. The Cordilleran ice sheet covered western Canada and southern
Alaska.
c. The Scandinavian ice sheet covered, well, Scandinavia and
northern Europe (the British Isles, northern France, Germany,
Poland, and western Russia.
d. The Kara ice sheet covered most of northern European Russia,
while the Barents ice sheet covered a lot of the Arctic north of
Scandinavia and European Russia.
e. The Inuitian ice sheet covered northernmost Canada .
f. The Antarctican ice sheet was much huger.
g. There were large glaciers in most mountain ranges.
h. I don't expect you to memorize these Pleistocene glaciers: I
was just trying to give you a sense of the scale of the
Pleistocene glaciation. Just remember that a large chunk of real
estate (30-35% of the land) was covered in Antarctica- and
Greenland-like ice sheets or in alpine glaciers. Later in the
semester, we'll cover glacial processes in more detail.

VIII.H means Highland climates. This is sort of a catchbag for the
microclimatic variation you get in mountains.
A. Climate in highlands is affected by the normal lapse rate, which makes
it colder and colder the higher up you go
B. It is also affected by aspect: Where the mountainside faces.
1. North-south aspect:
a. The side facing the equator is warmer and drier. This is called
the adrêt side (south-facing slope in the Northern
Hemisphere; north-facing slope in the Southern Hemisphere).
b. The side facing the poles is shaded and, so, cooler and moister.
This is called the ubac slope (north-facing slope in the
Northern Hemisphere; south-facing slope in the Southern
Hemisphere).
2. Windward-leeward aspect
a. Windward slopes are moister and more moderate in temperature
because they experience the uplift of humid air.
b. Leeward slopes are drier and hotter because of adiabatic heating
and drying of descending air. This is the rainshadow slope.
C. On a small-scale map, H climates are just shown as an undifferentiated
color (bright orange on the map above; often black on other maps).
Remember, though, that these are zones of unbelievably complex
microclimatic variation induced by elevation and aspect.

Well, that is one fast whirlwind tour of the world's major climate types. Be
able to recognize generally where you should expect to find each of them and
why: tropical rainforest, tropical monsoon, tropical wet and dry; tropical
desert, tropical semi-arid, temperate desert, temperate semi-arid; humid
subtropical, Mediterranean, west coast marine, temperate wet and dry; humid
continental; tundra; and frozen climates. You now know what to expect when
you travel and can pick vacation spots that have climates similar to other
places you like. Hey, you could do travel consulting! Our department does offer
a course, Geography 352,
Geography of Travel and Tourism.

Hey -- can anyone recognize the projection for the Köppen-Geiger map
above? No, I won't test you on it. Just hoping to make some older
information stick even if I don't test you! It was covered in the section on
maps.

Geography 140 Introduction to Physical Geography

Lecture: Climates

Geography 140
Introduction to Physical Geography