Download presentation
Presentation is loading. Please wait.
Published byGwendoline Curtis Modified over 9 years ago
1
spark.ucar.edu/workshops
3
Greenhouse Effect Review CO 2 absorbs heat in the atmosphere When heat accumulates in the Earth system, the average global temperature rises
4
Increased CO 2 & the Greenhouse Effect When the amount of carbon dioxide in the atmosphere increases, average global temperature rises. Longwave radiation emitted by CO 2 is absorbed by the surface, so average global temperature rises
5
Emissions -> More CO2 in Air -> Higher Temperature 15° 18°
6
Climate Sensitivity - definition Whenever the amount of carbon dioxide in the atmosphere doubles, average global temperature rises by 3 degrees Celsius. 15° 18° 15° 18°
7
Learning from the Past (ice cores) Ice age
8
CO 2 Emissions – Where are we now? In 2013, CO 2 emissions are around 10 gigatons (GtC) per year (10,000 million tons in units used on this graph)
9
CO 2 in Atmosphere – Where are we now? ice age 396 ppm in 2013 For hundreds of thousands of years, CO 2 varied between 180 and 280 parts per million, beating in time with ice ages Since the Industrial Revolution, CO 2 has risen very rapidly to about 400 ppm today
10
Math of Climate Sensitivity When the CO2 concentration in the atmosphere doubles, temperature rises by 3°Celsius (about 5.4°F) Examples: If CO 2 rises from 200 ppmv to 400 ppmv, temperature rises 3°C If CO 2 rises from 400 ppmv to 800 ppmv, temperature rises 3°C Note: as CO 2 rises from 200 to 800 ppmv (800 = 4 x 200), temperature rises 6°C ( = 2 x 3 degrees, not 4 x 3 degrees)
11
Climate Sensitivity Calculator demo spark.ucar.edu/climate-sensitivity-calculator
12
Climate Sensitivity Calculator Activity Use the calculator (previous slide) to determine the expected temperature for the various CO 2 concentrations listed in column 1 of the table above (students fill in column 2); then have them graph.
13
Advanced Climate Sensitivity Math T = T 0 + S log 2 (C / C 0 ) T : new/current temperature T 0 : reference temperature (e.g. 13.7 degrees C in 1820) S : climate Sensitivity (3 degrees C) C : new/current atmospheric CO 2 concentration C 0 : reference atmospheric CO 2 concentration (e.g. 280 ppmv in 1820) Example: What is new temperature if CO2 rises to 400 ppmv (from 280 ppmv)? T = T 0 + S log 2 (C / C 0 ) = 13.7 + 3 log 2 (400/280) = 13.7 + 3 log 2 1.43 = 13.7 + 1.54 = 15.2 degrees C
14
Dry air mass of atmosphere = 5.135 x 10 18 kg = 5,135,000 Gigatons CO 2 currently about 599 ppm by mass (395 ppmv) = 0.0599% CO 2 current mass = 0.0599% x 5,135,000 Gt = 3,076 Gt CO 2 current emissions = 9.5 GtC/year Atmospheric fraction = 45% M = M 0 + [0.45 x (3.67 x m)] = 3,076 GtCO 2 + [0.45 x (3.67 x 9.5 GtC/yr)] = 3,076 + 15.7 GtCO 2 = 3,092 GtCO 2 CO 2 concentration = 3,092/5,135,000 = 602 ppm by mass CO 2 concentration = (602/599) x 395 ppmv = 397 ppmv Math of CO 2 Emissions and Atmospheric Concentration (16 + 12 + 16) / 12 = 44/12 = 3.67 GtC vs GtCO 2
15
Poll: Rising Emissions B A C ? ? ?
16
B A C ? ? ?
17
B A C ? ? ? Poll: Emissions rise then steady
18
B A C ? ? ? Poll: Emissions rise then fall
19
Very Simple Climate Model demo spark.ucar.edu/simple-climate-model
20
Why does temperature continue to rise as emission rate declines? Atmosphere CO 2 in Atmosphere CO 2 Emissions CO 2 Removal by Oceans & Plants spark.ucar.edu/climate-bathtub-model-animations-flow-rate-rises-falls spark.ucar.edu/imagecontent/carbon-cycle-diagram-doe
21
Greenhouse Effect & Atmosphere Layers Model
22
Initial State Earth Lower Atmosphere Upper Atmosphere
23
Hour 1 – Step A - Radiate
24
Hour 1 – Step B - Absorb www.cmmap.org/scienceEd/summercourse/summerCourse12/docs/SaturdayAM.pdf spark.ucar.edu/events/workshop-nsta-national-2013-climate-models
25
Spark Workshops Sunday 8-9 AM: Using Scientific Field Campaigns to Learn About Weather and Climate - Convention Center, 006B spark.ucar.edu/workshops Spark Booth #1818 rrussell@ucar.edu eastburn@ucar.edu
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.