William Moomaw - Climate Advocacy: From Grassroots Activism to International Policy
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Additional reasons for rebuilding soils and ecosystems William Moomaw Biodiversity for a Living Climate Tufts University November 26, 2014
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Transcript of William Moomaw - Climate Advocacy: From Grassroots Activism to International Policy
Additional reasons for rebuilding soils and ecosystems
William MoomawBiodiversity for a Living Climate
Tufts UniversityNovember 26, 2014
The allocation of carbon (C) in the biosphere
• 800 GT of carbon is in the atmosphere as CO2
• Carbon in deep oceans is 37,000 GT and carbon in surface ocean is 1000 GT mostly as carbonate
• 2300 GT of C is found in soil• 500 GT is found in living organisms mostly in
forest trees
The amount of CO2 in the atmosphere depends upon rate of addition minus rate of removal
• Each year about 9 GT is released to the atmosphere by human activity from burning fossil fuels and deforestation and soil degradation
• About 3 GT of this is absorbed by the terrestrial biosphere
• About 2 GT is absorbed by the oceans• Net 4 GT is added to the atmosphere each year
Comparisons of sinks
• Burning all fossil fuels would add 12.5 x the current amount of CO2 to the atmosphere
• Burning all forests and plants would add 0.63 x current amount
• Adding all soil carbon would add 2.9 x current amount
The goal
• The ultimate objective of this Convention … is to achieve … stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.
• Such a level should be achieved within a time-frame sufficient to allow ecosystems to adapt naturally to climate change, to ensure that food production is not threatened and to enable economic development to proceed in a sustainable manner.
Strategies
• Reduce the 9 GT of carbonfrom human activity– Rapidly reduce use of fossil fuels– Avoid releasing carbon dioxide (and methane)
from soils and plants• Accelerate the uptake of carbon dioxide in
soils and plants by restoring forests, grasslands, wetlands and soils
Think of CO2 in the Atmosphere as a Bathtub
Emissions
CO2 in the atmosphere
Net Removals
As long as emissions per year exceed removals, the level of water (CO2) in the bathtub continues to rise.
The tub is filled by emissions and drained by net removals into oceans and biomass.
The inflow is roughly double the outflow
Reducing Emissions Post 2050 Puts Us On Track to Levelize CO2 around 550 ppm
The “flat path” plus post 2054 reductions
Emissions exceed net removals all the way to 2100!
Fossil Fuel Emissions
24 B
18 B
12 B
6 B
0
2000 2020 2040 2060 2080 2100
TonC
/yea
r
CO2 in the Atmosphere800
700
600
500
400
300
2000 2020 2040 2060 2080 2100
ppm
The outcome of the “flat path” plus post 2050 reductions
Goal
What Happened? Why Didn’t Emissions Level?
Total Emissions and Removals
24 B
18 B
12 B
6 B
02000 2020 2040 2060 2080 2100
TonC
/yea
r
Despite reductions, Emissions exceeded Net Removals through 2100.
CO2 in the atmosphere will rise until the two meet.
CO2 in the Atmosphere
800
675
550
425
300
2000 2020 2040 2060 2080 2100
Goal
Emissions
Net Removals
It Will Take an 80% Reduction in Fossil Fuel Emissions
At this point, emissions equal net removals by 2050!
Fossil Fuel Emissions
24 B
18 B
12 B
6 B
0
2000 2020 2040 2060 2080 2100
TonC
/yea
r
CO2 in the Atmosphere800
700
600
500
400
300
2000 2020 2040 2060 2080 2100
ppm
Goal
• Approximately one-third of 230 GT carbon dioxide added to the atmosphere is from soils
• Need to shift to restorative development, mobilize the biosphere and accelerate carbon storage in plants and soils
• NOTE! Carbon removal from the atmosphere to the soils happened slowly, but can be released rapidly
• Can we accelerate the uptake?
Aggressive Sequestration can boost removals
Sources of Total Removals6 B
4.475 B
2.95 B
1.425 B
-100 M
1900 1930 1960 1990 2020 2050 2080Time (year)
TonC
/yea
r
Biomass + soils
oceans
seq.
Results with 80% reduction in fossil fuel emissions plus 1.6 GTC/year in additional sequestration by 2050
CO2 in the Atmosphere800
700
600
500
400
300
2000 2020 2040 2060 2080 2100
ppm
Goal
The Added Sequestration Boosts Net Removals
Total Emissions and Removals24 B
18 B
12 B
6 B
0
2000 2020 2040 2060 2080 2100
TonC
/yea
r
Net Removals without additional sequestration
Net Removals with additional sequestration
So CO2 in the atmosphere balances out a little earlier and lower
Another problem
• “This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop.”
• Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years.
• S. Soloman et al, PNAS, 2009)
Note that CO2 persists for morethan a millennium after emissions cease at the peak, and temperatures remain high.
Only a restored global biosphere can accelerate the removal of carbon dioxide from the atmosphere
• We cannot accelerate the uptake of carbon dioxide from the atmosphere by the oceans
• We can only increase the rate of uptake by plants and soils
• To avoid irreversible climate change restorative development to rebuild forests, grasslands and wetlands and their soils is not an option
• It is an essential imperative!
Let us begin NOW!
