Post on 19-Aug-2018
GEOG 1300, Sec 001, Spring 2010
Weather & Climate
M-W 12:00-13:50, Brewster B-102
Tropical Storm Eugene
Hurricane Emily
July 19, 2005
Dr. Hong-Bing Su
Department of
Geography
(1) Student Survey
(2) Course Overview
(3) Introduction to Weather & Climate
Lecture #01
January 11, 2010, Monday
(1) 1300. Weather and Climate (4) (F,S,SS) (FC:SC)
(2) Introductory survey of meteorology including
weather and climate principles, processes, and
patterns, at a variety of scales from local to global.
(3) It is the first course in atmospheric sciences.
(4) Emphasis on North America.
Course Descriptions
(1) The first course in Atmospheric Science.
(2) A prerequisite for core courses of the undergraduate
Certificate in Atmospheric Science offered by the
Department of Geography at ECU.
(3) Currently being reviewed at NC GA: a B.Sc. degree
in Applied Atmospheric Sciences.
More about this Course
(1) GEOG 3510 Physical Meteorology
(2) GEOG 3520 Dynamic Meteorology
(3) GEOG 3550 Principles of Synoptic Meteorology
(4) GEOG 4510 Meteorological Instruments & Observations
Four Core courses required for the
Certificate in Atmospheric Science
(1) M-W 12:0013:50
(2) Office hours: TuTh, 11:0013:00
or by appointment
(3) 14 Mondays, 14 Wednesdays
(4) These schedules are subject to cancellations
announced by the university (e.g., adverse weather)
Course Schedule
(1) Total 3 exams: 2 mid-term exams (20% each)
Final exam (30%).
(2) In-class and take-home exercises count for 30%.
(3) Exams are generally non-cumulative, but none of
the exams can be dropped.
(4) All exams are close-book, no paper nor electronic
notes will be allowed.
(5) A make-up exam may be offered ONLY if a
verifiable and university allowed excuse, such as a
doctor’s note, is provided to the instructor.
Exams
(1) A: 85% and higher
(2) B: 70% and higher
(3) C: 55% and higher
(4) D: 50% and higher
(5) F: Below 50%
Grade
Each exam of the entire class may be adjusted (curved)
based on all scores.
(1) Attendance is required.
(2) Students need to sign the attendance sheet in each
class.
(3) For each missing class that is not excused, 1-point
will be deducted from your final course grade.
Today is exempted as the first day of class.
(4) Same excuses allowed for make-up exams apply.
Attendance Policy
Course Webpage
http://core.ecu.edu/geog/suh/Courses/Courses.html
Password: Weather2010Su/index
Global
Circulation
Hurricane Floyd September 15, 1999
What is this?
Extratropical cyclones, sometimes called
mid-latitude cyclones or wave cyclones
Mid-latitude Cyclones
Typical winter mid-latitude cyclone paths
Tornado
Thunderstorm
Lightning
Conversion between Temperature Scales
oF = 9 / 5 oC + 32
oC = 5 / 9 ( oF – 32 )
K = oC + 273.16
oC = K – 273.16
Old formula (1945): Twc = 0.0817(3.71V0.5 + 5.81 – 0.25V)(T-91.4)+91.4
New
formula:
The smaller the solar angle, the greater area of beam spreading
Beam Spreading
A
C
B
BC
AB= sin ( = solar angle)
Stefan-Boltzmann Law:
The radiation intensity ( I ) in unit of W m-2 from a body with an absolute temperature T (in unit of K) is proportional to the 4th power of T:
Radiation Properties & Principles
I = ε σ T4
σ = the Stefan-Boltzmann constant in W m-2 K-4
ε = emissivity
Blackbodies (perfect emitters, ε = 1), Graybodies (ε < 1)
Indices of Water Vapor Content in the Atmosphere
mv
mq = =
Specific humidity q (g kg-1)
Mixing ratio of water vapor r (g kg-1)
mv = mass of water vapor
md = mass of dry air
m = mass of atmosphere
mv
mv + md
mv
md
r =
Relative humidity (RH) is the percentage of actual water vapor content in the air relative to that (maximum water vapor content) in saturated air.
Indices of Water Vapor Content in the Atmosphere
e
es
RH =
x 100%
q
qs
r
rs
x 100%
x 100%
RH =
RH =
Atmospheric pressure
= gravity
x density of mercury
x height of mercury
Weight = gravity
x density
x volume
volume = height x area
pressure = weight / area
Measurement of
Atmospheric
Pressure
Mercury
Barometer:
Basic Definitions: Atmosphere
A gaseous envelope gravitationally bound to a celestial
body (e.g., a planet and its satellite in the solar system).
Different atmosphere have very different properties.
The atmosphere of Venus is very thick and cloudy, and
is responsible for its very high surface temperature by
virtue of the greenhouse effect. On the other hand, the
Martian atmosphere is very sparse.
Earth’s atmosphere is intermediate between the above
two extremes, distinguishing from all other atmospheres
by its very active hydrologic cycle. Water plays a very
important energetic role and a crucial factor to the
existence of severe storms in the Earth’s atmosphere.
Basic Definitions: Weather
The state of the atmosphere, mainly with respect to its
effects upon life and human activities.
As distinguished from climate, weather consist of the
short-term (minutes to days) variations in the
atmosphere.
Popularly, weather is thought of in terms of elements
like temperature, humidity, precipitation, cloudiness,
visibility, and wind, at a given time and locations.
As used in the taking of surface weather observations,
a category of individual and combined atmospheric
phenomena that must be drawn upon to describe the
local atmospheric activity at the time of observation.
Basic Definitions: Climate
The slowly varying aspects of the atmosphere-
hydrosphere-land surface system.
It is typically characterized in terms of suitable averages
of the climate-system over periods of a month or more,
taking into considerations the variation in time of these
averaged quantities. Climate classifications include the
spatial variation of these time-averaged variables.
Beginning with the view of local climate as little more
than the annual course of long-term averages of surface
temperature and precipitation, the concept of climate has
broadened and evolved in recent decades in response to
the increased understanding of the underlying processes
that determine climate and its variability.
Basic Definitions: Climate System
The system, consisting of the atmosphere,
hydrosphere, lithosphere, and biosphere,
determining the Earth’s climate as the result of
mutual interactions and responses to external
influences (forcing).
Physical, chemical, and biological processes
are involved in the interactions among the
components of the climate system.
Basic Definitions: Meteorology
The study of the physics, chemistry, and dynamics
of the Earth’s atmosphere, including the related
effects at the air-earth boundary over both land and
the oceans.
Fundamental topics include the composition,
structure, and motion of the atmosphere.
The goals ascribed to meteorology are the complete
understanding and accurate prediction of
atmospheric phenomena.
In popular usage, the underlying science of weather
and weather forecasting.
Basic Definitions: Climatology
The description and scientific study of climate.
Descriptive climatology deals with geographic and temporal
distributions of meteorological observations over a specific
period of time.
Scientific climatology addresses the nature and controls of
the Earth’s climate and causes of climate variability and
climate change on all time scales.
Modern treatment of the nature and theory of climate must
deal with the dynamics of the entire atmosphere-ocean-land
surface climate system, in terms of its internal interactions
and its responses to external factors.
Applied climatology addresses the climate factors involved
in a broad range of problems relating to the planning, design,
operations, and other decision-making activities of climate
sensitive sectors of the modern society.
Basic Definitions:
Atmospheric Science
The comprehensive study of the physics,
chemistry, and dynamics of the Earth’s
atmosphere, from the Earth’s surface to
altitudes of several hundred kilometers, this
usually include atmospheric chemistry,
aeronomy (physics and chemistry of the upper
atmosphere), magnetospheric (plasma)
physics, and solar influences on the entire
region.
Meteorology vs. Climatology
What are the main differences?
Meteorology– weather
– instantaneous state of
the atmosphere
– Forecast of changes
over short time period
– For example, daily, 3-5
day weather forecast
Climatology– climate
– statistical properties of
the atmosphere (mean,
variance, extremes)
– Long term characteristics
of a place
– For example, monthly
average or more.
IPCC 2007Components in Climate Change Modeling
(1) What are the differences between weather and
climate?
(2) What are the differences between meteorology,
climatology, and atmospheric sciences?
(3) True or False:
Floods are the most deadly weather events.
Questions
(4) Multiple Choice:
Which of the following weather events costs the
most financial loss?
A) Tornado
B) Hurricane
C) Lightning
D) Extreme Heat
Questions