Download WebText- GEOGRAPHY OF UTAH

WebText- GEOGRAPHY OF UTAH
Chapter 7 –Utah Geography and Utah’s Atmosphere (including Utah’s weather and long-term
climate)
DRAFT webtext by G. Atwood, 2012
Use with professional courtesy and attribution including attribution of original sources where indicated.
LINK to printable version… it may differ a bit from this web-posted version.
CHECK THIS
Subtitle:
Utah, the greatest snow on Earth… since when and for how long?
BIG CONCEPTS: This chapter explores Utah’s atmosphere, including its interactions with Utah’s physical
geography and Utah’s human geography.
1.
The ATMOSPHERE is the third of the five subsystems of Earth systems. It controls weather and
climate.
2.
Utah has four regions based on today’s climate
3.
Climate changes… we change climate… climate changes us.
4.
Concepts of atmospheric science include: spatial differences due to LOCATION; importance of The
Gas Law; and effects of scale
5.
Planetary setting affects Utah’s weather and climate.
6.
The atmosphere is a subsystem of Earth systems, and is a system itself with feedback loops.
(No #7)
8.
Earth’s oceans control global climate… we call us Planet Earth… Planet Water.
9.
Closed-basin lakes – historians of climate change, short term and long term. Global inter-glacial,
Holocene Great Salt Lake.
10.
Ice Age Lake Bonneville (global glacial, Pleistocene Lake Bonneville)
11.
What’s known about present trends; global and local climate change
12.
Air Quality and Utah geography
13.
Citizen weather watchers have abundant resources on the web.
EVIDENCE. Examine these images for spatial patterns related to weather and climate (the Atmosphere)
WSU-BYU-Greer-AtlasUT_p055 -4-climate-regions
WSU-BYU-Greer-AtlasUT_p070 -annual-snowpack
Anderson-national-sunshine
Anderson-National precip
NOAA-National precip
NOAA – Temperatures – US mean temperatures (west vs east)
Utah-Annual Temp WSU-BYU-Greer-AtlasUT_p 060
Utah Annual Precip WSU-BYU-Greer-AtlasUT_p 066
Quotation:
Meteorologists quip: “Climate is what you expect… weather is what you get.” from
(www.wasatchweatherweenies Steenburgh UofU)
LINK to The 15 Words of GEOG3600 and version that can be printed.
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CASES:
Case 1: 2002 Olympics 2/11/2002
Case 2: 2012 regional snowpack / water content 2/11/2012 NRCS
Joyous blog for daily "cases" blog by Jim Steenburgh, UofU meteorology... –
www.wasatchweatherweenies
Topics… Questions to Ponder –
What would make the best record of climate change? Why has Utah, arguably the best (most complete,
most detailed, longest, and academically interesting) record of climate change in western North America?
How does weather/climate impact you.
What would it take to convince you that only 15,000 years ago, climate was markedly different that today?
What would it take to convince you that only 100 years from now, climate may be just enough different to
require changes in life style?
Why is the atmosphere the most dynamic of Earth systems subsystems?
Overarching Goal of the Chapter:
Become a citizen-geographer with respect to the Earth systems, specifically with respect to Earth’s
atmosphere. Monitor weather, appreciate weather, and understand climate the way you might try to
understand football. Be able to tell your grandchildren what it was like in the year 2112… y2020, y2030 etc.
Be able to explain the issues, the changes, the surprises, and how it affected you. The issues are playing
out before you, on your “home field.”
MAJOR CONCEPT:
Utah is located, today, where three weather systems converge: winter low pressure wet weather systems
from the northwest and west; springtime and early summer monsoonal systems that sweep eastward the
state bringing in tropical air masses; and occasional bouts of Arctic air from Canada and the Midwest that
cross the Rockies and bring cold cold weather. Topography and present weather systems result in Utah’s
having four climate zones. But it hasn’t been that way for very long and won’t stay that way. Because the
atmosphere has little mass, it is the most dynamicof the subsystems of Earth systems with dramatic
consequences especially to the hydrosphere, the biosphere that depends on the hydrosphere, and the
anthrosphere that is accustomed to present conditions. Ice Age Lake Bonneville was not way way long ago.
It is not from the age of the dinosaurs. Only 15,000 years ago, Marriott Library was underwater and the
UofU might have had a mastodon for its mascot.
Specifics: by the end of this chapter… you should:
 Understand some basics about the ATMOSPHERE (weather and climate) such as the structure of
the atmosphere, what causes winds to blow.
 Understand some of the reasons for the spatial patterns of Utah’s present day weather and
climate.
 Understand the concept of “where weather is born” and how important oceans are to weather and
climate.
 Gain skills of an amateur climate geographer, at about the level of Monday evening quarterbacks…
high interest but not necessarily highly skilled.
 Be able to explain how Lake Bonneville and Great Salt Lake are historians of climate change and
what some of the changes have been.
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


Be able to explain evidence for changes in present-day climate and why climate scientists are
concerned.
Know the changes that are expected to happen to Utah due to climate over the next couple
hundred years.
Choose whether to be a citizen-scientist who informally recognizes change.
Coaching for students of UofU GEOG3600-Geography of Utah:
Ask yourself “why” questions. Why? Because why questions explore causality. Why are there more regions
in Utah associated with climate than with the geosphere? Why does the wind blow? Why has Utah the
Greatest Snow on Earth?
Forever remember what weather is like this year… and years to come.
Terms to understand with respect to ATMOSPHERE and Utah geography
Climate
Weather
Climate change
Ice Age global glacial climate
Today’s global interglacial climate
Lake Bonneville
Global warming
Greenhouse effect
Wind Anderson, wind pressure differences
Winter low pressure systems
Summer monsoons
Arctic blasts
Evaporation
Transpiration
Precipitation
Greatest Snow on Earth
Desert climate zone
Steppe climate zone
Humid continental climate zone
Upland or montane climate zone
THEORY / CONCEPTS towards an understanding of ATMOSPHERE and geography of UTAH
1. The ATMOSPHERE is the third of the five subsystems of Earth systems. It controls weather
and climate.
IMAGES
Atmosphere - Earth's safety blanket -- Anderson 1975 Layered
Moran and Morgan 1995- Global circuation explained
Skinner1999-Global Circulation Cells
Skinner1999-HighsLows
Chason book cvr 1997
The ATMOSPHERE is the subsystem of Earth systems that includes the gaseous Earth, weather, and
climate. The atmosphere is the Anthrosphere's security blanket! It is the gaseous envelope that protects us
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from inhospitable radiation and regulates Earth's temperature. It makes life as we know it possible... and life
has greatly affected it. The atmosphere is dynamic and closely coupled with the hydrosphere, biosphere,
anthrosphere, and geosphere. Earth a system with subsystems that interact. The atmosphere is the 'most'
dynamic of Earth's subsystems because it has so little mass. To understand climate and weather, it helps
to understand the atmosphere and its association with: solar energy, Earth's rotation, and gravity.
Abundant evidence, some of it from Utah, indicates that changes of global temperatures of a few degrees
hotter or colder cause major shifts of weather patterns and related interactions with Earth systems. Colder,
wetter, more seasonal resulted in Ice Age Lake Bonneville at its height only 15,000 years ago. A few
degrees hotter would change timing and amounts of precipitation, and effect quality of life resulting in Utah
being more like Arizona of today.
2. Utah has four regions based on today’s climate
Atlas of Utah – WSU-BYU-Greer images
Precipitation p 066 ; and Evaporation p 61
On DEM
Utah’s present day climate results in four climate zones classified based on the ratio of precipitation to
evaporation:
Desert = at least twice the amount of evaporation than precipitation
Steppe = evaporation exceeds precipitation but not by two-times evaporation.
Montane = precipitation exceeds evaporation
Humid continental = hot dry summers and cold wet winters (along the Wasatch Front and windward side of
some other-wise steppe zones).
REGIONS, Ch05 of this text, delineate boundaries based on meaningful criteria. What are the meaningful
criteria for drawing climate zones for Utah? It takes judgment to choose criteria that can be objectively
applied and that carry meaning.
Four climate zones based primarily on: world wide recognized classificaitons; and based on the ratio of
evaporation and precipitation.
Atlas of Utah , by Arlo Richardson, former State Climatologist. LINK to Atlas p. 55
Desert = Average annual precipitation is less than half of annual potential evaporation. Average annual
precipitation is on the order of 5 – 8 inches / year.
Steppe = Average annual precipitation is less than annual potential evaporation but not less than half.
Average annual precipitation is on the order of 8 – 14 inches / year.
Highland AND humid continental = Average annual precipitation exceeds average annual potential
evaporation. Average annual precipitation of mountains of the Wasatch Front and of the High Uintas is over
40 inches / year.
33% of Utah is true desert LINKS … HAMBLIN Basin and Range, Tule Valley; Canyonlands
Hot summers, cold winters… colder winters by latitude and elevation
St George … mean annual temperature 61.5 degrees
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24% of Utah is highland (montane) climate, LINKS … HAMBLIN High terrain of Rocky Mountain
physiographic province, e.g., Mt Powell; and High Plateaus of Colorado Plateau plus outlier mountains of
Colorado Plateau
40% of Utah is intermediate, steppe - Grand Staircase … HAMBLIN Semi-arid. Discuss DRC hemi-arid Mostly in regions of freezing winters
3% of Utah is the humid continental of Wasatch Front LINK … HAMBLIN SLC Mt Olympus
Cold winters
Hot summers
Present climate: Weather hazards and Utah: not tornado alley; winter: avalanches and slick roads;
summer: lightning and flash floods.
Climate hazards: wet cycles: flooding and landslides; dry cycles = drought
3. Climate chages… we change climage… climate changes us.
BRAC executive summary
BRAC long report
Climate change may be the single greatest issue facing society over the next few decades. Climate change
makes winners and losers. What will happen to Utah’s geographies, human and physical. Utah’s closedbasin lakes are historians of climate change, their sediments record conditions at the time they were laid
down. Utah’s Great Salt Lake is the global interglacial lake of the Bonneville Basin. Lake Bonneville was
the global glacial Ice Age lake of the Bonneville Basin. Science of the past 30 years has dramatically
expanded our knowledge of how and why these lakes evolve. Science of the next 30 years will clarify
forcing factors and feedback loops of climate change and the five subsystems of Earth systems. Each of us
will make a difference: some more so than others.
4. Concepts of atmospheric science include: spatial differences due to LOCATION; importance
of The Gas Law; and effects of scale
5. IMAGES
GA-Gas Law
Skinner1999-Global Circulation Cells
Anderson - Sunlight for US
WSU-BYU-Greer-AtlasUT_p057 sky Cover
What is Climate? … long term weather. The origin of word “climate” in Greek is the same as for an incline…
it means “angle.” Even the Greeks of thousands of years ago understood that the angle of sunlight, due to
Earth’s tilt caused seasonality. Winter is due mainly to TILT of Earth's axis not due to proximity to the sun.
Uneven distribution of heat drives and modifies climate and weather. Uneven distributions include: (a)
contrasts of the poles versus the tropics; (b) contrasts between continents versus oceans; and (c) local
contrasts of cold versus warm air masses association with elevation, and (d) of course, seasonal variations.
The Gas Law.
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Think about a hot-air balloon and how it is controlled. The temperature and volume of the air in the balloon
is adjusted with respect to the temperature of the surrounding air. Hot air is less dense than cold air… the
cold air is pulled down more effectively by gravity, and the balloon squirts up. It’s a bit more complex than
that… but intuitively easy to understand given every day examples of it from cooking to auto mechanics.
(P)(V) = (constant)(T).
P = pressure
V = Volume
T = Temperature
Pressure is a force per unit area; barometric pressure measures the weight of the column of air being held
up by an area of Earth's surface (such as your head). When people goes up an elevator of a skyscraper
and their ears pop... what is happening?
Winters have less intense sunshine. Continental landmasses of mid-latitudes (Utah’s location) become cold
compared to oceans. Summers have more intense sunshine and longer days. Land masses heat up
(differentially) changing the heat and density of associated air masses. Air masses follow the rules of the
Gas Law, all in a global context. Wind results pressure / density difference: wind blows from regions of
higher pressure to lower pressure. As air masses travel through the atmosphere, they change temperature
and volume. This affects additional relationships. Think systems: systems have subsystems that interact,
and interact as feedback loops.
Ocean currents also are driven by density differences that include thermal differences and differences in
salinity.
http://oceanservice.noaa.gov/education/tutorial_currents/05conveyor2.html
Ocean currents act as a ribbon of conveyor belts that redistribute Earth’s heat. So do currents of the
atmosphere. The jet streams are like commanders of armies (weather systems) that collide as fronts. The
weather systems sling air masses from “where weather is born” across Utah bringing highly variable
conditions.
Scale (a concept discussed in Ch01: Location) is particularly important to atmospheric scientists because
the consequences of global processes can differ markedly from microscale. Geographers and climate
scientists recognize a special special problem… MAUP - Modified Area Unit Problem. It means that scale
actually changes results. Planetary weather isn’t just the sum of local weather. Utah is affected by planetary
patterns (global scale such as contrasts of equator versus poles); by continental or oceanic scale (synoptic
patterns such as the jet stream); by regional scale phenomena (mesoscale) such as weather fronts; and
local scale (ground level or micro-weather) that can have economic consequences such as consequences
to raising crops.
6. Planetary setting affects Utah’s weather and climate.
IMAGES
NASA - Ocean Conveyor Belt
NASA Seabed Sediments OxIsotope Stages -- getting outdated
GLOBAL
Structure of the Atmosphere – compare structure of the geosphere – structure of the hydrosphere.
Anderson - Layered. LINK to animation of layers.
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Sunshine and Latitude – seasonality (amount of sun and variability of sunshine)
Planetary circulation Moran and Morgan -Planetary circulation
Utah is mid-latitude. – Example St. George.
GoogleEarth / NASA / Christopherson nifty displays
OCEAN SCALE (Synoptic)
Oceans vs Continents – potential precipitation – where weather is born (see below)
Utah is continental… far from oceans.
Temperture patterns… NOAA
Where weather is born: Moran and Morgan - Air Mass Source
Location in northern hemisphere, mid latitude… so most weather come to us from the west. … the
Pacific…. Dominates.
Economics: Winter, low pressure systems, mostly from the north west (born in cold, maritime conditions)
bring snow to our ski resorts. High pressure systems (and geosphere and anthrosphere) keep an
atmospheric lid on inversions.
Oceans - water heat capacity. global patterns of oceans vs continents; GoogleEarth - live... perhaps Change patterns ... change weather... dramatically Moran and Morgan Summer HiLo
ENSO, El Nino, La Nina http://www.jpl.nasa.gov/earth/ocean_motion/el_nino_index.cfm
REGIONAL SCALE (Mesoscale)
Geosphere: Topography (GEOSPHERE). Mountain terrain disrupts patterns.
•
Eastern US, climate zones run east-west. Broad. Gradational. Perpetual sunshine in the south, frigid
winters in the north. Simple pattern, broad bands. Even precipitation: NOAA - US precipitation
•
Western US, climate zones run north-south. Parallel the Pacific Ocean, the Cascades and Rocky
Mountains,
The Rocky Mountains shelter the West from most arctic blasts of cold… but not all
LOCAL SCALE
Canyon winds… on and off shore breezes of GSL.
GSL Steenburgh et al – lake effect http://wasatchweatherweenies.blogspot.com/2012/02/newperspectives-on-lake-effect.html
Water sources – Anderson U.S. Precip
Barriers – Anderson RainShadow
7. The atmosphere is a subsystem of Earth systems, and is a system itself with feedback
loops.
Image
Utah weather systems.
Where weather is born Moran and Morgan Air Mass Source
Utahns have traditionally looked at weather and climate from the perspective of water, specifically,
precipitation. Water availability impacts economies as diverse as skiing and raising cattle.
Three weather patterns bring us the weather we talk most about:
•
Winter, low pressure, wet weather systems from the northwest that bring us the greatest snow on
Earth.
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•
Spring and summer Arizona-Mexico monsoons that sweep west to east across the state with rolling
thunderstorms, local downpours, lightning. Oceans are cold compared to continents, the regional pattern is
from oceans straight across the continents, from more dense to less dense. The flow is called zonal
because it tends to be from west to east without the great meridianal swings of winter storms.
•
Cold Arctic blasts from Canada’s mid continent usually stay east of the Rockies, but when they
don’t they deliver bitter cold weather, hazardous to man and beast.
How do these systems operate?
Remember the Gas Law… colder is colder is more dense... thicker is more mass. So... the same volume of
cold air mass exerts more pressure than a warm air mass; AND a thicker mass of air exert more pressure
(referred to by weather folks as a ridge of high pressure) than a thinner mass of air (referred to by weather
folks as a trough of low pressure). SkinnerHighsLows
High pressure systems are driving downward, and spin, because Earth is a globe, clockwise from the
perspective of looking down on them. Usually cold air is being pulled downward. Winter high pressure
systems tend to bring clear cold skies, clear because the water vapor in them is not condensing.
Low pressure winter weather systems are rising upward and spin counter-clockwise. Skinner 1999 High
Low. These systems pick up moisture from oceans and other surface sources and as the humid air rises, it
cools, and water vapor condenses. Thus Utah’s low pressure systems are our winter storms, preceeded by
south winds, accompanied by snow or rain, and finishing with blasts of cold north air.
The pressure systems direct air masses. AIR MASSES are masses of air with internally similar
temperature, pressure, moisture content, and stability. Weather systems control the paths of air masses.
Note the major storm tracts of western US. Storm tracks are typical paths that storms take. Observe how
Utah is under-represented on this map.
Warm air masses and cold air masses get caught up in weather systems. FRONTS when air masses
collide. Many weather terms come from World War I and World War II as weather became better
documented but still largely not understood. The terms are highly descriptive. With World War II,
phenomena such as the jet streams were recognized and super-generals controlling the lesser-generals,
the weather systems.
8. Earth’s oceans control global climate… we call us Planet Earth… Planet Water.
Images
NASA Blue Marble
NASA – Ocean Conveyor Belt
NASA – Sea Sediments OxIsotope Stages (may be out-dated graph)
Climate change is a fascinating academic science in addition to a practical one. Some of the climate work
is being done at the UofU, much of it is done at institutions with ocean-going vessels… because, to
understand climate of the past, present, and future, it seems essential to understand the coupling and
interactions of oceans and the atmosphere.
Five big concepts:
First: Oceans redistribute heat around the globe. When ocean currents are not transferring heat, the planet
goes into an ice age. When would oceans not transfer heat? Consider the arrangement of continents
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around the globe. Note how loopy the currents must be to transfer heat. Thus, the first principle of climate
change is about the GEOSPHERE and tectonics. Some millennia the potential for Ice Ages are greater
than others becsuse of the distribution of continents. Present-day arrangements of continents can cut off
ocean circulation… leading to an Ice Age.
Second: What does it take with respect to present-day configurations to have the conveyor belt of ocean
currents not function? Think about what makes the currents move? In part it is wind… but mostly it is
density differences… the same processes that drive wind. Salt water is more dense than fresh and tends to
drop to low places of the oceans. Warm water is less dense and tends to float on the surface. Thus the
ribbon of ocean circulation rises and falls and loops around present day continents. But if density
differences become minimal… the conveyor belt has problems.
Third: Cooling of global temperatures by a few degrees happens every several thousand years in a
convergent of cycles called the Milankovitch ____. The more seasonal the Earth’s climate, the more likely
an Ice Age, so variations in the tilt of Earth’s orbit affects global temperatures. The more ellipsoidal Earth’s
orbit (variation from perfectly circular) the more likely an Ice Age. The position of the Earth (how the tilt
faces the sun) also affects global temperatures. Each of these factors is on its own schedule, and about
every 100,000 years, the three converge to make Earth a few degrees cooler, the ocean currents don’t
redistribute ocean heat, and Earth goes into a global glacial time. Note: this is not Icebox Earth with a
totally frozen land surface. Some areas are more affected than others: for example, continents are more
affected than oceans, but even oceans are affected. For example, the water that is transferred to
continental glaciers is sufficiently great that sea level lowers about 200 feet. There have been at least 40
global glacial ice ages over the past few million years. They are recorded in deep sea sediments, and the
last couple cycles, in ice cores. CHECK THAT. Thus, global climate, and climate in Utah, has oscillated
from global glacial to global interglacial over the past few million years.
Fourth: Heating of global temperatures occurs in a few ways. The first is discussed (above) based on
relationships of Earth with the sun. But other ways include changes to the atmosphere, specifically, the
ratio of gases in the atmosphere. Earth’s atmosphere has evolved over its four-five billion year history.
Present day components of the atmosphere, discussed earlier in this chapter, have kept Earth in a
temperature range that has supported the diversity and abundance of life of the past 10,000 years. If Earth
did not have an atmosphere, Earth would be hostile to life. The present mix works well to support flora and
fauna and keep Earth warm via the Greenhouse Effect. A greenhouse works by letting in wavelengths of
visible light, converting the light into infrared (heat) energy, and trapping the infrared energy in the
greenhouse. Some gasses of Earth’s atmosphere are greenhouse gasses meaning they pass incoming
visible light and trap outgoing infrared energy, meaning heat. Why would small changes in amounts of
gasses matter to the balance? Because the atmosphere has so little mass, the addition of a mass of gas to
it has much more effect than adding that same mass, for example to the oceans. There is no doubt that the
atmosphere of Earth was much more rich in carbon dioxide when dinosaurs roamed and coal fields formed
by the millions of tons. But humans weren’t part of the ecosystem then… and our life styles wouldn’t just
have had to accomdate dinosaurs, we would have had to adapt to a climate very different from our present
one.
Fifth: Abundant evidence documents changes in atmosphereic greenhouse gasses, changes in sea ice,
changes in extent of glaciers. There is almost no argument that Earth’s climate is warming. The vast
majority of scientists who study climate see a causal correnation between human activities and global
warming. This is my favorite UofU-generated summary of evidence and choices:
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LINK to David Chapman's index page of lectures / talks http://thermal.gg.utah.edu:80/talks/index.html
What evidence of changed climate, past, present and future might there be in Utah?
Where would one look for materials that might record climate change to colder, global glacial Ice Age
conditions? As stated quite a few times in this text, Earth scientists would look at sediments that record
condiditons of when they were deposited. To have a good record…
(a) conditions have to be right to have sediments deposited;
(b) there has to be datable material in them; and,
(c) conditions need to be right to preserve them.
For example: we can assume:
salt deposits record exceptionally hot / dry conditions.
moraines (deposits of glaciers) record cold / wet conditions.
extensive dust / wind deposits record windy, dry conditions.
And certain vegetative evidence records … environmental conditions… as do animal remains.
9. Closed-basin lakes – historians of climate change, short term and long term. Global interglacial, Holocene Great Salt Lake.
Images:
Historic Great Salt Lake… 1961? dry times; 1987 wet times images images
Hydrograph of Great Salt Lake
USGS real time hydrograph http://ut.water.usgs.gov/greatsaltlake/index.html
The Water Equation
GSL Watersheds USGS
GSL up and down balance Fry pan versus test tube... extend into West Desert and stabilize
GSL H2O up down
Brainstorm wet cycle options results West Desert Pumping plan
What Utah has, better than any other place in western North America, is a place (Great Salt Lake) that
captures sediments, continuously: the Bonneville Basin. We call the most recent global glacial Ice Age lake
of the Bonneville Basin Lake Bonneville. We call the present-day global interglacial lake, Great Salt Lake.
The water equation: GA-Water Equation. Applied to Great Salt Lake … change in extent of GSL... UGS
photomosaic 1960s versus image 1986
Precipitation of 1980s; Excess precip by month (precip over average); Precipitation vs lake level 1980s;
GSL map of inflows and variability; GSL in 1987; Flooding of Duck Clubs; Brainstorm how to control. LINK
to water balance of Great Salt Lake . Waters in... evaporation out...
Great Salt Lake - Lake Bonneville are historians of climate change.
GSL of present climate. Lake Bonneville of Ice Age climate.
What does it take to have a lake… (a) a basin to hold water; and (b) water into the basin.
Closed basins (important) think tectonics
Not dried out (important) ... depositional Hamblin Bear River Delta;
Lake sediments of shorelines and the lake bed record conditions at the time they were deposited.
Shorelines
Joyous dissertation research... coastal processes of Great Salt Lake... hazards...
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Historic hydrograph… http://ut.water.usgs.gov/greatsaltlake/index.html
10. Ice Age Lake Bonneville (global glacial, Pleistocene Lake Bonneville)
Images
MAP 73 – good observations (Don R Currey’s mapping of shoreline evidence) underpin good science).
GK Gilbert Lake Bonneville location map
Ice Age – Lake Bonneville
Shoreline evidence Hamblin Point of Mountain; Sketch by CB Hunt.
Antelope Island ... 5 levels all in one image WhRxToSouth
Hydrograph of Lake Bonneville. Extent of Lake Bonneville.
Compare Lake Bonneville and GSL, Map 73
GA – AI images.
STORY of LAKE BONNEVILLE: SETTING... Repeat… what does it take to have a deep lake? A basin to
hold it and water to fill it. Utah’s geosphere, Basin and Range extension, provides the basin. Cold wet
climate provided the water.
HYDROGRAPH from Map 73 ... and from Wambeam... to Hamblin
33,000 years ago... lake about the size and shape of Great Salt Lake but not called Great Salt Lake
28,000 years ago, lake on the rise in responce to climate change (from hot dry "global interglacial" to wet
cold "global glacial")
26,000 - 22,000 years ago Stansbury level... it's a big lake and hangs out at this level more than once. This
is the level of the floor of Cache Valley.
16,000 - 14,500 years ago Bonneville level. The lake drops about 32f ft (100 m) from the Bonneville level to
the Provo level by a catastrophic flood.
14,500 - 13,000 years ago Provo level
Before 12,000 LOW LEVEL. The lake drops from the Provo level to even below the present level of Great
Salt Lake by climate change (from cold wet of "global glacial" to warm dry of "global interglacial")
12,000 - 10,000 years ago rise to Gilbert
10,000 years ago to present Great Salt Lake
Lake Bonneville is an interesting story… and one that is relevant: topography, scenery, hazards, resources;
groundwater aquifers, not the water, but the materials; climate science… by understanding the past, can
appreciate the present and anticipate the future. The Lake Bonneville – GSL story also indicates how
climate can change dramatically. The drop due to climate change from Ice Age Lake Bonneville at the then
level of 4800 ft a.s.l. to average levels of historic Great Salt Lake at about 4200 ft a.s.l. took less than a
thousand years. Local researches call it “the salinity crisis” because, from a fresh water fish perspective, it
would have been a total change of environment. The change of climate mode from global glacial to global
interglacial was indeed global, with evidence from cores of ocean sediments of the North Atlandic and
elsewhere that show lifeforms of cold waters changing to a suite of life forms of warmer waters; ice cores
from Greenland and from Antarctica that show changes in snow – ice accumulation; and changes in lake
sediments that indicate changes of vegetation pollen to drier species and suites of lake algae that live in
warmer waters.
The record of Lake Bonneville – Great Salt Lake probably is the best record of climate change of inland
western North America. It is complete, detailed, multi-parametered and has been studied by numerous
researchers. The lake sediments record details of present climate as well as past climate. For example,
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lake sediments record changes in water quality associated with human settlement and resource extraction.
Great Salt Lake will become a valuable historian of future changes of climate by lifeforms of its sediments
and sediments of its shorelines.
11. What’s known about present trends; global and local climate change
BRAC Science Report
Dave Chapman's index page of lectures... http://thermal.gg.utah.edu:80/talks/index.html
Climate change appears likely to be the major social and political issue of the end of the 21st century,
assuming present trends and present human habits continue. How will these trends affect Utah, and when.
LINK to Blue Ribbon Advisory Committee http://www.deq.utah.gov/BRAC_Climate/final_report.htm and to
SCIENCE REPORT from their website. In 2009... students of GEOG3600 read the BRAC report "critically"
meaning... not to criticize it, or "believe it" or "not believe it" but to understand what it was saying. HOW to
read critically: LINK TO McCOY's coaching of UofU graduate students.
Present global climate trends are projected to affect Utah’s geosphere, hydrosphere, (atmosphere of
course), biosphere, and anthrosphere… meaning all subsytems of Earth systems. The consequences will
indirectly affect each of the themes of social and behavioral science we will explore in the third part of this
text.
Projected impacts to Utah’s geosphere: the geosphere is the most massive, least reactive subsystem of
Earth’s system. Will Utah’s landforms or rock materials change? Probably, not much. Other places on Earth
that lose their glaciers will have increase ground failures and stream incision, but Utah has experienced hot
dry conditions (based on cores of Great Salt Lake) and effects on the geosphere are (a) not well defined,
(b) not anticipated as major. Certainly climate projections will not have the effects that the change to global
glacial conditions of the Ice Age had with its glaciers, increased sedimentation.
Projected impacts to Utah’s hydrosphere: the atmosphere drives precipitation rates, types, and seasonality
in Utah. Climate models are mixed for what areas of Utah will be affected and how. Increased atmospheric
temperatures indicate and atmosphere with more energy and the capacity to hold considerably more water
vapor. As a sweeping generalization, climate will change as though latitude has shifted, meaning Canada
will experience climate somewhat analoguous to the US Midwest, Utah will experience weather that is now
south of us. Weather systems and timing of weather patterns are expected to change particularly in places
such as Utah where more than one weather system results in sesonaally contrasting precipitaiotn.
Meaning, timing and amount of snowpack runoff could change significantly. Northwestern US is projected
to be hotter and wetter. For example, The Cascades may become bare of snow for years on end but
streams run fuller and with more flooding events. Southwestern US is projected to become hotter and drier.
Will the Arizona-Mexico monsoons move north consistently into Utah? Good question. Water agencies
discuss consequences to wet water and to water rights. Will Lake Powell or Lake Mead become enormous
siltation sinks? Will Upper Basin Colorado River states continue to honor commitments to California based
on dramatically different water runoff? Utah’s rates of evaporation already far exceed annual precipitation,
so the proportional increase in potential evaporation may not affect actual evaporation in Utah as it will in,
for example, Iowa or CHECK THAT.)
Projected impacts to Utah’s weather and climate. The most agreed-upon projection is that Earth surface
temperatures will warm as global atmosphere warms. Projections are that global warming will be uneven.
Oceans will not warm as much as continental land surfaces. Projections are for more extreme weather
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events, such as more vigorous hurricanes. Changes in the arctic will be greater than along the Equator. For
Utah, the projection is average annual temperature gains of 1 degree by 20XX and two degress by 21XX.
Projected impacts to the biosphere: Just because we can’t anticipate with much certainty what many effects
will be, doesn’t’ mean we don’t anticipate significant consequences. Changes in the Arctic will be more
severe than elsewhere. What about Utah? Fire frequency and magnitude are expected to increase due to
increases in temperatures and changes in the vigor of forests. For example, the life cycles of some insects
may result in deforestation. Other species may be winners.
Projected impacts to the anthrosphere are the most varied: some projections are that humans are so
adaptable that we will thrive with the challenges of changed enviroments. There will be winners and losers
globally and locally. For example, Midwestern breadbasket of the US may shift north to Canada. As a
sweeping genalization, projections indicate stressed nations will be more stressed. Al Gore and the IPCC
received the Nobel prize for peace. Indeed the most dire projections of effects of climate change increased
global inequalities and resulting conflicts over basic needs for water and food. How will Utah be effected?
We are a resilient state with commitment to community. We are where change has been accommodated
geologically for millions of years and socially for thousands of years. Perhaps we’ll do just fine if we learn to
recycle water the way water is recycled in closed systems of submarines. Perhaps we’ll enjoy Arizona
heat… or perhaps not.
Geographers and geographic thinking is playing a role in understanding, predicting, and anticipating
change. For example, physical geographers have spatial and statistical tools to address dynamic systems.
We can run and tinker with models with ease not anticipated even 50 years ago. We think about social
options and consequences and explore social and behavioral science issues. The October 2010 issue of
the Annals of the Association of American Geographers was devoted to climate change. Articles included a
wide range of physical and human geographies, such as: (a) projections of total land-surface precipitation;
(b) explorations of inherent conflicts of capitalism and environmentalism; and (c) effects on Inuit peoples of
changes to Arctic whaling. At least a dozen of the 30 CHECK THAT articles had relevance to Utah. For
example, an article on water projections of the Snake River discussed possible shifts in the location and
strength of El Nino / La Nina weather systems off the Pacific coast and how these systems had tied to past
climate patters. The changes of seasonal patterns of water balance for Blanding, UT and the Colorado
Basin were compared to the effects on the Great Lakes at Rensselaer, MN.
Summary: we live in interesting times that we effect and that affect us. To the extent that we can be
geograhers, meaning, “see, understand, and appreciate webs of relationships among peoples, places, and
environments” we can be empowered to participate with consciousness in our future.
12. Air Quality and Utah geography
Images
We breathe what we produce… and what Mother Nature produces. With or without climate change, Utahns
face issues of the atmosphere that our economy, health, demographics, and quality of life. Air quality is an
example.
BRIEF HISTORY OF AIR QUALITY AND THE WASATCH FRONT
(with thanks to XXX Dalley of Utah Department of Environmetnal Quality).
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1840s-60s
• Reports of pioneers as they headed across Great Salt Lake desert toward Pilot Peak, Nevada. So named
because it piloted them. Sometimes in the summer they couldn’t see the peak. Why?
1890s-1900
• Smoke corridor. Alfalfa farmers grumpy.
• 19 smelters in Salt Lake Valley
1910-15
• Legislation passed the Utah legislature to ban smelting of ores with greater than 20% sulfur. About half
the smelters shut down. Photographs of conditions. National example.
1900-40s
• Coal and fuel oil. Winter heating and industry.
• LOTS of particulates. Ash, soot, haze, smokes.
• SLC “smoke officer.”
• Spring-cleaning of my youth (1946-54) had real meaning.
• Stories of stratified snow / ash / snow.
• Kennecott and the Oquirrhs
1940s-50s
• Home heating: from coal and oil to natural gas
• Increase in automobile usage. Lessons of Los Angeles.
• 50 – 60 days per year that valley conditions exceeded today’s standards
• Kennecott and the Oquirrhs
1970s
• EPA regulations
• I&M standards (inspection and maintenance)
• Kennecott and the Oquirrhs
• Decrease in number of days per year that valley conditions exceed today’s standards
1980s
• Lots of days with inversions during the winter
1990s
• Relatively “clear” weather patterns
2000-present
Non-attainment areas
MAJOR HEALTH PROBLEMS - which counties...
Winter inversions
Summer ozone
Point sources...
MAP non-attainment areas
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The two, immediate, pressing air quality issues associated environemtnal quality along the Wasatch Front
are: summer ozone levels and winter inversions. Both phenomena are examples of interactions of the
geosphere, hydrosphere, biosphere, and anthrosphere with the atmosphere.
SUMMERTIME Ozone
Moran and Morgan, Night Day over lake
Lake / valley – Mountain breezes ... schematic for ocean... or for GSL MandM NightDay over lake
• Nighttime inversions over by 9 – 10 AM during the summertime.
• Vehicles emit chemicals that in 5-7 hours plus sunlight result in elevated ozone
• Morning rush hour along the Wasatch Front… which way are canyon and valley breezes blowing along
Davis, Salt Lake and Utah Counties?
• After 5 – 7 hours… what time is it and which way are the breezes blowing? Have you seen this?
• Most areas of U.S. don’t share this problem.
• Research by DEQ-AQ. Contract to North American Weather Consultants. Report of 1996 monitoring of
ground level ozone using a van, and higher altitude ozone using an airplane. Air masses are 1000s of feet
deep and can spill over into adjacent counties.
WINTER INVERSIONS: Winter: not flushed out so easily
Anderson, InversionInValley
Onton Inversion Image
Problems of
• Particulates
• Carbon monoxide
During spring, summer, and fall, warming of Earth’s surface by sunshine keeps valley air moving. But in the
winter, air can stagnate with cold air naturally staying in low places with an inverted layering of atmospheric
densities that are stable until flushed by strong frontal passage that “scoops” out the stagnant air mass OR
by heating of the valleys land surface that results in mixing air masses.
• Cold weather increases strength of inversions
• High pressure anticyclonic systems increase strength of inversions
• Snow cover increases strength of inversions
• Zonal versus meridional storm patterns (jet stream – wandering westerlies) increase strength of inversions
• Does pollution itself increase strength of inversions? Positive feedback loop? Probably.
13. Citizen weather watchers have abundant resources on the web
LINKS to a few of my favorite weather web sites
NOAA - Weather service - SLC International http://forecast.weather.gov/MapClick.php?site=slc&textField1=40.79&textField2=111.97&zone=1
NOAA- Weather service - discussion of weather
http://www.wrh.noaa.gov/slc/forecast/textproduct.php?pil=afd
DAILY weather map... and archived - http://www.hpc.ncep.noaa.gov/dailywxmap/
WIND across Great Salt Lake http://www.wrh.noaa.gov/slc/current/meso.nwut.php
REAL-TIME weather data and graphics NCAR http://www.rap.ucar.edu/weather/
DATA disaggregated... meaning you can see just temperature or just pressure
http://www.ametsoc.org/amsedu/dstreme/
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PREDICTION center National Weather Service - NOAA http://www.hpc.ncep.noaa.gov/
WESTERN REGIONAL CLIMATE CENTER - Desert Research Institute http://www.wrcc.dri.edu/
CLIMATOLOGY of the UNITED STATES http://www.ncdc.noaa.gov/oa/documentlibrary/clim81supp3/clim81.html
AIR QUALITY - real time - U.S. http://www.airnow.gov/
RADAR and emergency alert site - http://www.emergencyemail.org/weatherradarWANG1.asp?
SNOTEL - Trial Lake (Uinta Mountains, headwaters of Provo, Weber, and Duchesne Rivers)
1983; 2009, 2010
CURRENT WATER YEAR data - http://www.ut.nrcs.usda.gov/snow/data/current.html
Utah Water NEWS - http://utahswaternews.wordpress.com/ (many links)
DROUGHT monitor - http://drought.unl.edu/DM/
SNOWPACK - USDA - NRCS - http://www.wcc.nrcs.usda.gov/cgibin/westsnow.pl
And I'm sent this report every week... example for 2/22/2010
Weather Underground... a new site for me
http://www.wunderground.com/US/Region/US/2xFronts.html
FINAL SECTION OF THIS CHAPTER… So What?
Explore consequences of climate and weather (Earth’s subsystem of the atmosphere)
Present
Past
Future
Utah’s LOCATION make it a place sensitive to changes in climate.
Utah’s sense of PLACE tied to recreation … greatest snow on Earth; Utah’s Dixie a place for snowbirds
and golf all year long.
INTERACTIONS: Utah weather and climate is all about interactions of global, regional, and local conditions
and among all five physical geography subsysemt (geosphere such as terrain; hydrosphere such as
oceans; biosphere such as carbon sinks globally; and anthrosphere poor air quality).
MOVEMENT of wind and air masses is driven by density differences and gravity and affected by barriers.
Review Ch04 and recognize connections.
The atmosphere is the most responsive of the physical Earth subsystems (geosphere, hydrosphere, and
atmosphere) because it has little mass and therefore small changes are proportionately impactful.
Explore Utah’s weather and climate (atmosphere) and issues of social and behavioral sciences,
specifically: (economics; demographics; political science; sociology; and quality of life). Think present, and
consider consequences of projected climate change. What areas of Utah will be impacted the most by
increased temperatures, changed timing of runoff, fire, and / or drought?
LIST of “The 15 Words”
Loc
Place
Migra
Inter
Region
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Geo
Hydro
Atmo
Bio
Anthro
Econ
Demog
PoliSci
Sociol
QLife
SELF QUIZ
 What causes winds to blow.
•
Explain spatial patterns of Utah’s present day weather and climate.
•
Where is Utah’s weather “born” and why?
•
How would you rate your skills as an amateur climate geographer, about the level of Monday
evening quarterbacks?… high interest but not necessarily highly skilled.
•
Explain how Lake Bonneville and Great Salt Lake are historians of climate change and what some
of the changes have been.
•
Explain evidence for changes in present-day climate and why climate scientists are concerned.
•
What changes are Utah climate experts expecting to witness in Utah, assuming climate trends?
•
What could you do to be an informal citizen-scientist who informally recognizes change?
SUMMARY:
Utah’s location, mid-latitude, inland from oceans, and with varied topography sets broad parameters for
weather and climate (the third of the five subsystems of Earth systems, the atmosphere). Utah’s climate is
seasonal. Contrasting weather systems from the northwest and southwest bring contrasting types of
precipitation events. The Rockies largely protect Utah from fridgic Arctic blasts, but occasional winter
outbreaks can bring very cold weather into the state.
Utah’s present climate and its interactions with terrain result in four climate zones that range from dry
desert to heavy-snowpack montane. Statewide, Utah is classified as semi-arid that implies sort-of arid. A
better term might be hemi-arid, half arid, half not arid.
Immediate and longterm issues associated with the atmosphere impact human geography. Specifically, air
quality issues affect economics and health of most of Utah’s population. Climate change may be the single
greatest global issue facing the Nation and world. Consequences to Utah largely include projections on the
timing and type of precipitation. Increased tempertures will likely result in a shift from snow to rain and an
earlier snowmelt. Phenomena as varied as the economics of air conditioning and associated dependence
on energy, to prevalence of fire will be exacerbated by a Earth even a couple degrees warmer than now. All
projections show land masses affected to greater degree than oceans.
COURSE MANTRA: LINK
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