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 modified 2014.
Use
with professional courtesy and attribution including attribution of original
sources where indicated.
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.
7. Earth’s oceans control global climate…
we call us Planet Earth… Planet Water.
8. Closed-basin lakes – historians of
climate change, short term and long term. Global inter-glacial, Holocene Great
Salt Lake.
9. Ice Age Lake Bonneville (global glacial,
Pleistocene Lake Bonneville)
10. What’s known about present trends;
global and local climate change
11. Air Quality and Utah geography
12. 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
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.
CASES:
Case
1:
Case
2:
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.
·
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
Skinner1999-Global Circulation Cells
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 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
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
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.
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 closed-basin 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
IMAGES
Skinner1999-Global Circulation Cells
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.
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.
5.
Planetary setting affects
Utah’s weather and climate.
IMAGES
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.
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
Oceans
vs Continents – potential precipitation – where weather is born (see below)
Utah
is continental… far from oceans.
Temperture
patterns… NOAA
Where
weather is born:
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
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
Water
sources – Anderson U.S. Precip
Barriers
– Anderson RainShadow
6.
The atmosphere is a
subsystem of Earth systems, and is a system itself with feedback loops.
Image
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.
• 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
– 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 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:
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 inter-glacial,
Holocene Great Salt Lake.
Images:
Historic
Great Salt Lake… 1961? dry times; 1987 wet times
USGS real time hydrograph http://ut.water.usgs.gov/greatsaltlake/index.html
GSL Watersheds USGS
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)
Not
dried out (important)
Lake
sediments of shorelines and the lake bed record conditions at the time they
were deposited. Shorelines
Historic
hydrograph… http://ut.water.usgs.gov/greatsaltlake/index.html
10.
Ice Age Lake Bonneville
(global glacial, Pleistocene Lake Bonneville)
Images
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, 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
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 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).
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
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
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/
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
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.
