Download Carbon Lab - answers

THE CARBON LAB
This simulation explores global warming through its effect on the carbon cycle.
The solution to global warming? Just plant more trees? Read this slide and then comment on your answer
below.
http://www.slideshare.net/quercuscymru/carbon-uptake
Just plant more trees?
Although absorb CO2 from atmosphere and convert to plant tissue (carbon fixation) BUT in first five
years respiration = photosynthesis so effect is negligible.
After 5 years photosynthesis is greater than respiration so it does have an effect on carbon fixation
BUT the amount of trees needing to be planted and area needed is just too great to offset carbon – it
is better for preserving habitats/diversity.
**Often coniferous trees are planted as they grow quicker and can be harvested, but this can reduce
biodiversity/range of habitats**
Open up the simulation ‘’Carbon Lab” http://www.learner.org/courses/envsci/interactives/index.php
Syllabus excerpt:
Here we aim to explore how carbon emissions affect the carbon cycle and the complexity of the
processes involved.
DATA TABLES: CARBON CYCLE
LESSON 1: The Carbon cycle
Lesson 1:
Step 1
To Year
2000
2050
2100
Lesson 1:
Step 2
To Year
2000
2010
2020
2030
2040
2050
2060
2070
2080
2090
2100
Gaseous
Carbon
Atmosphere
700
863
1395
Ocean Water
Ocean
Surface
1000
1074
1197
Total
Carbon
Emissions
Gaseous
Carbon
Smokestack
Atmosphere
0
75
87
101
117
136
157
204
270
313
364
700
707
737
773
814
863
919
1002
1118
1247
1395
Deep
Ocean
38000
38189
38699
Fossil Fuels
Oil and
Gas
500
168
0
Ocean Water
Ocean
Surface
1000
1031
1039
1049
1061
1074
1089
1108
1136
1165
1197
Deep
Ocean
38000
38019
38049
38087
38133
38189
38255
38334
38433
38554
38699
Biosphere Gaseous Carbon
Coal
Soil
2000
1818
676
2000
2037
2098
700
752
833
Fossil Fuels
Oil and
Gas
500
452
396
331
255
168
66
0
0
0
0
Terrestrial Plants
Biosphere Gaseous Carbon
Coal
2000
1974
1943
1907
1866
1818
1762
1623
1353
1040
676
Soil
2000
2004
2012
2020
2029
2037
2046
2056
2068
2082
2098
Terrestrial Plants
700
714
724
733
742
752
763
775
792
811
833
Responses to questions
Step 1:
1. Perhaps minimal difference as terrestrial plants are not one of the bigger sinks.
2. Both increase at the same rate – perhaps run off of soil into ocean? Soil gets carbon input from decomposition.
3. Both increase, 1.5% rate for fossil fuel consumption, atmospheric carbon +23% 2050, +60% 2100. Positive correlation but
does not PROVE causation.
Step 2:
1. More carbon is fixed by flora as CO2 levels increase through photosynthesis – this can actually help growth? But depends on
deforestation levels staying the same?
2. Positive correlation – as emissions increase so does surface carbon in oceans – impacts on marine flora and fauna? –
oceans hold 50X more as a carbon sink than atmosphere – makes them more acidic affecting coral reefs – but as they warm
they absorb less CO2.
3. Excess carbon – in atmosphere – amounts doubling? Also deep ocean/surface ocean p139 Rutherford.
4. atmosphere and ocean surface – impacts are warming of both
Notes
DATA TABLES: CARBON CYCLE
LESSON 2: Curb emissions.
Lesson 2:
Step 1
To Year
2000
2050
2100
Gaseous Carbon
Atmosphere
700 (371ppm)
623 (337)
614 (332)
Ocean Water
Ocean Surface
1000
1008
1005
Lesson 2:
Step 2
To Year
2000
2050
2100
Deep Ocean
38000
38052
38072
Biosphere Gaseous Carbon
Soil
2000
2009
2005
Terrestrial Plants
700
708
705
Gaseous Carbon
Net Def.
Rate
-2.0
-2.0
-2.0
Fossil Fuel
% Increase
+2.5
+2.5
+2.5
Atmosphere
700 (370ppm)
945 (511ppm)
1510 (816ppm)
Deep Ocean
38000
38200
39001
Responses to questions
Step1:
1. They have reduced.
2. Soil/plants have increased – natural levels of cycle? Atmosphere reduced, ocean surface/deep increased but not as much.
Step 2:
1. Deep ocean is important as it tells us how much excess carbon is being absorbed here – also huge amounts of methane frozen in deep
ocean sediments – if these are released then can dramatically affect global temps.
2. It does decrease atmosphere levels and deep ocean levels of carbon significantly if deforestation is reduced and fossil fuel levels
reduce as well.
DATA TABLES: CARBON CYCLE
LESSON 3: Feedback effects
Lesson 3:
Step 1
To Year
2000
2060
2080
2100
Biosphere Gaseous Carbon
Net Def. Rate
-1.6
-1.6
-1.6
-1.6
Lesson 3:
Step 2
To Year
2000
2050
2100
Tundra
Melt
Rate
Net
Def.
Rate
-1.6
-1.6
-1.6
1
–—
3
Y
Y
Y
Soil
Gaseous
Carbon
1
-—
Terrestrial Plants
2000
2063
2085
2116
700
782
812
853
Ocean Water
Fossil Fuels
Atmosphere
Ocean
Surface
Deep
Ocean
Oil and
Gas
Coal
700
873
1409
1000
1076
1200
38000
38194
38717
500
168
0
2000
1818
676
6
Biosphere Gaseous Carbon
Soil
2000
2018
2060
Terrestrial Plants
700
754
836
Responses to questions
Step 1:
1. Carbon levels increase for both soil and flora.
2. carbon soils levels increase – increased uptake by plants therefore increasing flora levels.
3. decomposition rates may increase as increase temp favours more decomp and quicker recycling of nutrients. Human health
affected as disease vectors increase.
Step 2:
1. Large amounts of organic carbon are stored in the permafrost – this can be carried by rivers to the sea increasing surface
carbon levels – positive feedback loop
2. Both see large increases in atmospheric carbon levels. Also remember that methane as well as trapping heat is a carbon
compound (CH4).
Notes