Climate (Atms 4600) Professor Anthony R. Lupo Department of
Soil, Environmental, and Atmospheric Science University of Missouri
Columbia, MO
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ATMS 4600 Climate At the University of Missouri, I teach an
introductory climates class (too easy) and a graduate level class
(too hard). I wanted to create something in the middle. This class
will essentially just go 'upscale' from ATMS 8400 - Theory of the
General Circulation.
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ATMS 4600 Climate Some initial questions: What is Climate? How
does it differ from weather (synoptic, or even the General
Circulation)? How is this different from Climatology? Weather the
day to day state of the atmosphere. Includes state variables (T, p)
and descriptive material such as cloud cover and precipitation
amount and type, etc.
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ATMS 4600 Climate Recall in meteorology, we tend to divide
phenomena by scale based on what processes are important to driving
them. Table 1 ScaleTimeSpaceForceWeather Planetary7 14 days6000+
kmCo, PGFJet stream Synoptic1 7 days2000 6000 kmCo, PGF, Fric, Bouy
Low pressure Meso1 - 24 h10 2000 kmBouy, PGF, Fric Fronts Micro<
1 hr< 10 kmBouy, Fric, PGF Thunderstor m
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ATMS 4600 Climate Time / space Scales / example / forces Micro-
1 hour /
ATMS 4600 Climate General Circulation statistical features. We
think of planetary in scale, but time scales are 2 weeks, 1 month,
1 season, 1 year, a few years. Climate Is the long-term or time
mean state of the Earth-Atms. system and the state variables along
with higher order statistics. Also, we must describe extremes and
recurrence frequencies.
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ATMS 4600 Climate Thus, the general definition of climate is
scale independent and a technical definition would depend on your
scale, ie we can describe micro, meso, and synoptic climates and
climatologies. Climate as we will discuss it many contexts will be
"global" or large-scale in nature, or "upscale" in time from the
General Circulation.
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ATMS 4600 Climate FIG. 2.1. Annual global surface temperature
departures from the 1961 to 1990 average. [Sources: NOAA/ NCDC;
CRU/UKMO (HadCRUT3); and NASA GISS.]
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ATM 4600 Climate Observations and the Hockey Stick
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ATMS 4600 TemperaturePrecipitation
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ATMS 4600 Climate Climatology is the study of climate in a
mainly descriptive and a statistical sense. Climatologists study
these issues. Dynamic Climatology or Climate dynamics are
relatively new concepts and involve the study of climate in a
theoretical and/or numerical sense. In order to study climate in
this sense, we will use models, which will be derived using basic
equations. One way to accomplish this is via the scaling of
primitive equations, or using basic 'RT' equations (Energy Models,
which use concepts like Stefan Boltzman's law). We wont do this in
this class, save for ATMS 8600
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ATMS 4600 Climate Key concepts that will be discussed in this
course: We'll need to distinguish plainly between weather and
climate! (Review the concept of climatic averaging') We'll need to
talk about time variations on climate states ('climate' versus
climate change) We'll need to examine the components of the climate
system
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ATMS 4600 Climate We'll need to examine the state of the
climate, in particular this means 'internal variables' (internal
vs. external). We'll need to study climatic 'forcing' (this means
'external variables (e.g. Solar, Plate tectonics, humans?), (also
how they differ from internal)) We'll need to examine issues
surrounding spatial resolution and climatic character.
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ATMS 4600 Climate The earth-atmosphere system, courtesy of Dr.
Richard Rood.
(http://aoss.engin.umich.edu/class/aoss605/lectures/)
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ATMS 4600 Climate The primary components of the Climate system
1.The Atmosphere (typical response time --> minutes to three
weeks) 2.The Ocean (typical response time months and years, for
upper ocean) 3.The litho-biosphere (we'll treat as one for now)
4.The cryosphere (both land and sea ice, response times on order of
decades to MYs)
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ATMS 4600 Climate Aside: Typical short-hand notations used now
in the study of climate: 10,000 Years Before present (10 KY BP) KY
= Thousands of years BP = before present MY = Millions of
years.
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ATMS 4600 Climate Another view of the climate system
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ATMS 4600 Climate Another view
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ATMS 4600 Climate Each component of the climate system can be
described by it's own state variables, which are considered
internal variables. External forcing is defined as forcing outside
the system or sub-system. Thus, SST anomalies are internal or state
variables for the earth atmosphere system, or the ocean. But they
are considered 'forcing' or external to the atmospheric component.
Also, the dynamics of the internals are fairly well know, but heat
and mass exchange processes between sub-sytems not well
understood.