Transcript Lecture 1 - Department of Meteorology and Climate Science

METR 112 Global Climate Change
Professor Menglin Susan Jin
San Jose State University, Dept of Meteorology and Climate Science
www.met.sjsu.edu/~jin
Outline of today’s lecture
1. Introduction and Welcome
2. Discussion on the “greensheet”
3. Learning Contract
4. First glance on observations of Changing Climate
For greensheet, class ppt notes
http://www.met.sjsu.edu/~jin/METR112fall2011.htm
NOT any other websites!
About Professor
1.
A very good scholar www.met.sjsu.edu/~jin
Research projects: funded by NASA, NSF, Department of Defens
On land surface climate change, urbanization, remote sensing
20 leading author papers on top journals
2.
3.
to be an effective teacher
Goal
METR112 will help you to know the fundamentals of
global climate system,
climate change,
and gain appreciation of the complexities involved with climate change issues
Homework: 20%
Midterm Exam: 20%
Class Participation 5%
Group Project: 20%
Final Exam: 35%
Scale: 90+ A, 80’s B, 70’s C, 60’s D, <60 F
Homework will be assigned on Tuesdays in class
collected in discussions on two weeks later.
Content
1. Knowledge on Climate System:
Atmosphere Structure
Land Surface Properties
Land-Ocean-Atmosphere Interaction
Global Energy Balance
Global Hydrological Cycle
C cycle
Glacier
Aerosols and clouds
Ozone
2. Past Climate Change
3. Recent Climate Change
4. Climate Modeling – Its basics and Uncertainty
5. Climate Feedback
6. Urban Climate Change – Land Cover Change
7. Climate Change and Human Health
8. Remaining Questions on Global Climate Change Research
9. 10 Things You can do to Fight Climate Change
Lecture Hour:
TTH session
METR112
10:30 – 11:15 AM
Place:
DH515
Office Hour: 1 PM‐2:30 PM, Wednesday
9:50 -10:20 AM, Tuesday
more (TA)
Place: MSJ’s Office (DH613)
TA: Terrence Mullens
TA’s email:
"Terrence Mullens“[email protected]
TA’s office: DH619
•I will meet with you for extra office hour whenever you need.
•send email for appointment.
I am approachable!!!
References (not a text book):
“Understanding Weather & Climate” by
Edward Aguado and James E. Burt (Third Edition)
(cheap!)
Video collections: http://www.met.sjsu.edu/metr112-videos/
Useful materials will be assigned on webpage/homework/class
Learning Contract
• Instructor
– On time and prepared.
– Answers questions.
– Approachable and friendly.
– Fair with assignments and grades.
– Genuinely concerned about your learning and
intellectual development.
Learning Contract
•
Students
– Make every effort to arrive on time; and if late, enter class
quietly.
– Preserve a good classroom learning environment by
–
–
–
–
a) refraining from talking when other people are
talking
b) turning off cell phones.
Be courteous to other students and the instructor.
Aware that learning is primarily their responsibility.
Aware of universities policy on academic integrity and
pledge to abide by them at all times.
Have read and understand what plagiarism is and know
how to cite sources properly.
Academic Integrity
• Integrity of university, its courses and
degrees relies on academic standards.
• Cheating:
– Copying from another’s test, cheatsheet etc.
– Sitting an exam by, or as, a surrogate.
– Submitting work for another
• Plagiarism:
– Representing the work of another as one’s own
(without giving appropriate credit)
Plagiarism
• Judicial Affairs
http://sa.sjsu.edu/judicial_affairs/index.html
• Look at the Student Code of Conduct
• Read through SJSU library site on
Plagiarism
http://www.sjlibrary.org/services/literacy/info_comp/plagiarism
.htm
• http://turnitin.com/
GreenSheet (see handout)
• Homework online turnin (D2L)
• Class Participation
• Research Project
• Final grade
Let’s see some key global change observations….
.
.
Change in surface temperature in 20th century
Two main points in this figure
• Global mean surface temperatures have
increased 0.5-1.0°C since the late 19th
century
• The 20th century's 10 warmest years all
occurred in the last 15 years of the century
Note: 1. why is global mean?
2. what is surface air temperature? (see next few slides)
Temperature is measured
by
therometer
Thermoeter is required by WMO (see next slide)
World Meteorological Organization (WMO) http://www.wmo.int/pages/index_en.html
Weather station
http://www.nationmaster.com/encyclopedia/Image:Translational-motion.gif
Observed temperature changes
Warming
due to El Niño
Cooling
due to La Niño
1992-93
Cooling due to
Mt. Pinatubo
•Global mean surface temperatures have increased 0.5-1.0°C since the late 19th century
•The 20th century's 10 warmest years all occurred in the last 15 years of the century
Why does this matter? (important!)
• Such an increase continues. The best scientific estimate is that
global mean temperature will increase between 1.4 and 5.8 degrees C
over the next century as a result of increases in atmospheric CO2 and
other greenhouse gases. This kind of increase in global temperature
would cause significant rise in average sea-level (0.09-0.88 meters),
and other severe consequences
•Mean increase means that many regions increases much higher, and these regions
have problems in terms of extreme heat, drought, flood.
1979
2003
The Land and Oceans have both
warmed, but…
Important point of this slide
• Although global mean surface has been
warming up, for each region the change
can be different! (can be no change,
warming, or cooling)
Class activity: find out your grandpa’s hometown and see how
the temperature is changed there?
Antarctic Ice Shelves
• Most common Ice
Shelf: Giant floating
platform of ice formed
from glaciers located
along coastlines
• 50-600 meters thick
• Can last for thousands
of years
• 10 major ice shelves in
Antarctica
Larsen Ice Shelf Break
Then and Now


Temperature rises have
also led to the expansion
of species ranges in
Antarctica.
“Long term monitoring of
continental Antarctic
terrestrial vegetation is
crucial for accurate
measurement and
predictions of vegetation
dynamics in response to
future temperature
regimes around the world”
The “Keeling curve,” a long-term record of atmospheric CO2
concentration measured at the Mauna Loa Observatory (Keeling et al.).
Although the annual oscillations represent natural, seasonal variations,
the long-term increase means that concentrations are higher than
they have been in 400,000 years.
Graphic courtesy of NASA’s Earth Observatory.
Still going up!
CO2 Unit
atmospheric concentrations of CO2 in units of parts per million by volume (ppmv).
Each ppmv represents 2.13 X1015 grams, or 2.13 petagrams of carbon (PgC)
in the atmosphere
Atmospheric CO2 concentrations rose from 288 ppmv in 1850 to 369.5 ppmv in 2000,
for an increase of 81.5 ppmv, or 174 PgC. In other words, about 40% (174/441.5)
of the additional carbon has remained in the atmosphere,
while the remaining 60% has been transferred to the oceans and terrestrial biosphere.
http://www.esrl.noaa.gov/gmd/ccgg/trends/
Atmosphere Composition and Structure
Vertical Layers of the Lower Atmosphere
Atmospheric Properties vs. Altitude
Table 1: Composition of the Atmosphere
Gas
Percentage
by Volume
Nitrogen
78.08
Oxygen
20.95
Argon
0.93
Trace Gases
Carbon dioxide
Methane
Ozone
Chlorofluorocarbons
Water vapor
0.038
0.00017
0.000004
0.00000002
Highly variable
(0-4%)
The early Greeks considered "air" to be one of four elementary
substances; along with earth, fire, and water,
air was viewed as a fundamental component of the universe.
By the early 1800s, however, scientists such as John Dalton recognized
that the atmosphere was in fact composed of several chemically distinct gases,
which he was able to separate and determine the relative amounts of within
the lower atmosphere. He was easily able to discern the major components
of the atmosphere: nitrogen, oxygen, and a small amount of something incombustible,
later shown to be argon. The development of the spectrometer in the 1920s
allowed scientists to find gases that existed in much smaller concentrations in the
atmosphere, such as ozone and carbon dioxide. The concentrations of these gases,
while small, varied widely from place to place. In fact, atmospheric gases
are often divided up into the major, constant components and the highly
variable components, as listed below:
Although both nitrogen and oxygen are essential to human life on the planet,
they have little effect on weather and other atmospheric processes.
The variable components, which make up far less than 1 percent of the
atmosphere, have a much greater influence on both short-term weather and
long-term climate. For example, variations in water vapor in the atmosphere are
familiar to us as relative humidity.
Water vapor (H2O), CO2, CH4, N2O, and SO2 all have an important property:
they absorb heat emitted by the earth and thus warm the atmosphere,
creating what we call the "greenhouse effect." Without these so-called
greenhouse gases, the surface of the earth would be about 30 degrees
Celsius cooler - too cold for life to exist as we know it.
Global warming, on the other hand, is a separate process that can be caused by
increased amounts of greenhouse gases in the atmosphere.
The Greenhouse Effect (Important concept)
www.eecs.umich.edu/mathscience/funexperiments/agesubject/lessons/images/diagrampage.html
Greenhouse gases (important!)
CO2
CH4
N2O (Nitrous Oxiode, so called “laughing gas”)
CFC
O3
H2O
by the early 21st century,
N2O had become nearly as important a greenhouse gas as methane.
Their best guess was 0.7°C for N2O, and 0.3°C for methane. Wang et al. (1976).
atmosphere is not uniform
•temperature decreased with altitude
division of the atmosphere into
layers based on their thermal properties.
Troposphere: surface to12~18Km
all weather occurs
temperature decreases with
-6.5° C/kilometer (average!)
Stratosphere: 18-50km
temperature increase due to
ultraviolet (UV) absorption
by Ozone (O3)
Mesosphere 50-80km
Thermosphere
The outermost layer of the atmosphere,
where gas molecules split apart into ions.
http://www.visionlearning.com/library/module_viewer.php?mid=107
Vertical Layers of the Lower Atmosphere
Vertical Layers of the Lower
Atmosphere
Greenhouse
Gases are here
Greenhouse Gases
•
•
•
•
•
Carbon Dioxide
Methane
Nitrous Oxide
CFCs (Chlorofluorocarbons)
Others
Water vapor is one greenhouse house gas (GHG)
In fact, it is the most abundant GHG
Methane
Anthropogenic Methane
Sources
• Leakage from natural gas pipelines and
coal mines
• Emissions from cattle
• Emissions from rice paddies
Nitrous Oxide N2O
Anthropogenic Sources of
Nitrous Oxide
• Agriculture
• Bacteria in Soils
• Nitrogen fertilizers
CFCs (Chlorofluorocarbons)
CFC-11
CFC-12
Sources of CFCs
• Leakage from old air conditioners and
refrigerators
• Production of CFCs was banned in 1987
because of stratospheric ozone
destruction
– CFC concentrations appear to now be
decreasing
– There are no natural sources of CFCs
One World
World Population 6,446,131,400
Human activities
change environment
Class Participation
Name_________
1. Can you understand today class?
2. What is the surface temperature change
from 1990 – 2000?
3. How did you know of this class?