The Contribution of Agriculture, Forestry and other Land Use activities to Global Warming, 1990–2012

TLDR: These results are useful to further inform the current climate policy debate on land use, suggesting that more efforts and resources should be directed to further explore options for mitigation in agriculture, much in line with the large efforts devoted to REDD+ in the past decade.

Abstract: We refine the information available through the IPCC AR5 with regard to recent trends in global GHG emissions from agriculture, forestry and other land uses (AFOLU), including global emission updates to 2012. Using all three available AFOLU datasets employed for analysis in the IPCC AR5, rather than just one as done in the IPCC AR5 WGIII Summary for Policy Makers, our analyses point to a down-revision of global AFOLU shares of total anthropogenic emissions, while providing important additional information on subsectoral trends. Our findings confirm that the share of AFOLU emissions to the anthropogenic total declined over time. They indicate a decadal average of 28.7 ± 1.5% in the 1990s and 23.6 ± 2.1% in the 2000s and an annual value of 21.2 ± 1.5% in 2010. The IPCC AR5 had indicated a 24% share in 2010. In contrast to previous decades, when emissions from land use (land use, land use change and forestry, including deforestation) were significantly larger than those from agriculture (crop and livestock production), in 2010 agriculture was the larger component, contributing 11.2 ± 0.4% of total GHG emissions, compared to 10.0 ± 1.2% of the land use sector. Deforestation was responsible for only 8% of total anthropogenic emissions in 2010, compared to 12% in the 1990s. Since 2010, the last year assessed by the IPCC AR5, new FAO estimates indicate that land use emissions have remained stable, at about 4.8 Gt CO2 eq yr−1 in 2012. Emissions minus removals have also remained stable, at 3.2 Gt CO2 eq yr−1 in 2012. By contrast, agriculture emissions have continued to grow, at roughly 1% annually, and remained larger than the land use sector, reaching 5.4 Gt CO2 eq yr−1 in 2012. These results are useful to further inform the current climate policy debate on land use, suggesting that more efforts and resources should be directed to further explore options for mitigation in agriculture, much in line with the large efforts devoted to REDD+ in the past decade.

Figures

FIGURE 1

FIGURE 2

Table 1. Emissions by recent decade and in 2010 (Gt CO2 eq).

Table 2. Share of AFOLU and its sub-components to total anthropogenic emissions, by decade and for 2010.

Table 3. Aggregated share of AFOLU and its sub-components to total anthropogenic emissions, using the three main datasets available in IPCC AR5 WGIII

Full text

Tubiello, F. N., Salvatore, M., F. Ferrara, A., House, J. I., Federici, S.,
Rossi, S., Biancalani, R., D. Condor Golec, R., Jacobs, H., Flammini,
A., Prosperi, P., Cardenas-Galindo, P., Schmidhuber, J., Sanz
Sanchez, M. J., Srivastava, N., & Smith, P. (2015). The Contribution
of Agriculture, Forestry and other Land Use activities to Global
Warming, 1990-2012.
Global Change Biology
,
21
(7), 2655-2660.
https://doi.org/10.1111/gcb.12865
Peer reviewed version
License (if available):
CC BY-NC
Link to published version (if available):
10.1111/gcb.12865
Link to publication record in Explore Bristol Research
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The Contribution of Agriculture, Forestry and other Land Use activities to Global
Warming, 1990-2010: Not as high as in the past
1
Title Page
i. Title:
The Contribution of Agriculture, Forestry and other Land Use activities to Global Warming,
1990-2012: Not as high as in the past
ii. Running Title:
The Contribution of AFOLU to Global Warming
iii. Authors:
Francesco N. Tubiello
1*
, Mirella Salvatore
1
, Alessandro F. Ferrara
1
, Simone
Rossi
1,2
, Riccardo Biancalani
1
, Rocio D. Condor Golec
1
, Sandro Federici
1
, Heather
Jacobs
1
, Alessandro Flammini
1
, Paolo Prosperi
1
, Paola Cardenas
1
, Josef
Schmidhuber
3
, Maria J. Sanz Sanchez
4
, Pete Smith
5
, Jo House
6
, Nalin Srivastava
7
iv. Institute or Laboratory of Origin:
1
Climate, Energy and Tenure Division, Food and Agriculture Organization of the United
Nations, Via Terme di Caracalla, Rome 00153 Italy. Francesco.tubiello@fao.org ph: +39 06
57052169
2
European Commission Joint Research Center, Ispra (VA) 28100 Italy.
simone.rossi@jrc.eu.europa.eu; ph: +39-0332-78-3080
3
Statistics Division, Food and Agriculture Organization of the United Nations, Via Terme di
Caracalla, Rome 00153 Italy; josef.schmidhuber@fao.org; ph: +39 06 570 56264
4
Forest Management Division, Food and Agriculture Organization of the United Nations, Via
Terme di Caracalla, Rome 00153 Italy; maria.sanzsanchez@fao.org; ph: +39 06 570 54587
5
Institute of Biological and Environmental Sciences, School of Biological Sciences,
University of Aberdeen, 23 St Machar Drive, Room G45, Aberdeen AB24 3UU, Scotland,
UK. pete.smith@abdn.ac.uk, ph: +44 1224 272703

The Contribution of Agriculture, Forestry and other Land Use activities to Global
Warming, 1990-2010: Not as high as in the past
2
6
School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS,
UK. jo.house@bristol.ac.uk; ph: +44 117 954 5978
7
IPCC Task Force on National GHG Inventories, IGES, 2108-11 Kamiyamaguchi Hayama,
Kanagawa, Japan. srivastava@iges.or.jp, ph: +81 46 855 3754
v. Corresponding Author:
*
Francesco N. Tubiello, Food and Agriculture Organization of the United Nations, Via Terme
di Caracalla, Rome 00153 Italy.
email: francesco.tubiello@fao.org ph: +39-06-57052169
vi. Keywords: Agriculture, AFOLU, GHG, Emissions, Climate Change, Mitigation
vii. Type of Paper: Original Research

The Contribution of Agriculture, Forestry and other Land Use activities to Global
Warming, 1990-2010: Not as high as in the past
3
Abstract
We refine the information available through the IPCC AR5 with regards to recent trends in
global GHG emissions from agriculture, forestry and other land uses (AFOLU), including
global emissions updates to 2012. By using all three available AFOLU datasets employed for
analysis in the IPCC AR5, rather than just one as done in the IPCC AR5 WGIII Summary for
Policy Makers, our analyses point to a down-revision of global AFOLU shares of total
anthropogenic emissions, while providing important additional information on sub-sectoral
trends. Our findings confirm that the share of AFOLU emissions to the anthropogenic total
declined over time. They indicate a decadal average of 28.7±1.5% in the 1990s, 23.6±2.1% in
the 2000s, and an annual value of 21.2±1.5% in 2010. The IPCC AR5 had indicated a 24%
share in 2010. In contrast to previous decades, when emissions from land use (land use, land
use change and forestry, including deforestation) were significantly larger than those from
agriculture (crop and livestock production), in 2010 agriculture was the larger component,
contributing 11.2±0.4% of total GHG emissions, compared to 10.0±1.2% of the land use
sector. Deforestation was responsible for only 8% of total anthropogenic emissions in 2010,
compared to 17% in the 1990s. Since 2010, the last year assessed by the IPCC AR5, new
FAO estimates indicate that land use emissions have remained stable, at about 4.8 in 2012.
Emissions minus removals have also remained stable, at 3.2 Gt CO
2
eq yr
-1
in 2012. By
contrast, agriculture emissions have continued to grow, at roughly 1% annually, and remained
larger than the land use sector, reaching 5.4 Gt CO
2
eq yr
-1
in 2012. These results are useful to
further inform the current climate policy debate on land use, suggesting that as many efforts
and resources should be directed to agriculture mitigation in the coming years as they have
been devoted to REDD+ in the past decade, considering the increasingly larger emission
profile of crop and livestock activities compared to the forestry and land use change sector.

The Contribution of Agriculture, Forestry and other Land Use activities to Global
Warming, 1990-2010: Not as high as in the past
4
1. Introduction
Agriculture, Forestry and Other Land Use (AFOLU) activities generate greenhouse gas
emissions by sources as well as removals by sinks, through the oxidation and fixation of
organic matter via photosynthesis, followed by loss from decomposition and fire, including
complex microbial processes associated with human management and disturbance of
ecosystems. They comprise mainly non-CO
2
emissions by agriculture (CH
4
and N
2
O), and
CO
2
emissions by sources and removals by sinks by land use and land use change.
Assessing historical and current trends of AFOLU emissions, including agriculture
(crop and livestock production) and land use (land use land use change and forestry)
dynamics at global and regional level, is important both for science and climate policy. On the
science side, better data help to characterize anthropogenic forcing of the atmosphere, while
providing useful constraints to carbon cycle assessments. On the climate policy side, better
data provide support for concerted global action, allowing for transparent exchange of
information between parties, based on more accurate greenhouse gas inventories for reporting
under the United Nations Convention on Climate Change (UNFCCC). More reliable data, for
instance, provided the operational basis for implementation of the Kyoto Protocol First
Commitment Period, the adoption of the Bali Action Plan, and the Cancun Agreements.
Better AFOLU data specifically contributed to raising awareness on the need to reducing
emissions from deforestation and forest degradation (REDD+) (FAO, 2011). Indeed, early
quantifications of the share of deforestation to total anthropogenic emissions helped to make
the case for forests and the land use sector being as an effective, short-term climate change
mitigation option, compared to more complex and costly long-term measures in other sectors,
including agriculture (Stern, 2007).

Frequently asked questions

Q1. What is the main reason for the large component of FOLU emissions?

In fact, a large component of FOLU emissions are in any case driven by agriculture, in particular deforestation and peatland degradation. 

Q2. What is the share of AFOLU emissions to total anthropogenic emissions in 2010?

Results indicated that the share of AFOLU emissions to total anthropogenic emissions in 2010 was 21% rather than 24% and that agriculture (11%) has become as large a contributor to global emissions as forest and land usecombined (10%). 

Q3. What is the effect of the absolute trends in AFOLU?

These absolute trends, plus the fact that energy emissions continue to grow faster than those from AFOLU, result in decreasing shares of AFOLU compared to total anthropogenic emissions over time. 

Q4. What is the average FOLU emission in the last two decades?

recent FAO updates indicated that total FOLU emissions, as well asemissions from net forest conversion, which is a proxy for deforestation, remained stable in both 2011 and 2012 at their 2010 levels of 4.8 and 3.8 Gt CO2eq yr-1, respectively (FAOSTAT, 2014). 

Q5. What is the average share of AFOLU emissions in the last two decades?

Results (Tab. 3) indicated that the decadal average share of AFOLU decreased from28.7±1.5% in the 1990s, to 23.6±2.1% in the 2000s, and reached an annual value of 21.2±1.5% in 2010, lower than the 24% reported by the IPCC AR5 WGIII SPM. 

Q6. How much of the share of deforestation to total anthropogenic emissions was in 2010?

using the explicit information provided by the FAOSTAT database, ourresults further indicated that the share of deforestation to total anthropogenic emissions was a mere 7.9% in 2010.