The politics surrounding climate change is getting murkier by the day as a few indusrialised countries insist on using forests to combat global warming. The debate over the use of these forestswhich absorb carbon dioxide and are called 'carbon sinks'almost single-handedly sunk the latest round of negotiations on climate change in November 2000 (see 'Hold up'Down To EarthVol 9No 15December 312000The negotiations reached a deadlock because countries could not agree on the extent to which 'natural sinks' could be used to mitigate carbon dioxide emissions under the Kyoto Protocol.<>
A 'sink' for carbon dioxide is a natural system which absorbs more carbon dioxide than it releases during a given time period. This includes the oceans and terrestrial sinks. The protocol commits industrialised countries to cut emissions of greenhouse gases (ghgs) by a fixed percentage during a commitment period of 2008-2012. At the heart of the controversy lies the insistence of a group of industrialised countrieslike the us and Japanon using sinks to meet their reduction commitmentswithout curbing emissions from fossil fuel. The European Union (eu) and group of 77 developing countries (g77) oppose this move because there are too many unresolved questions related to sinksin terms of the modalities of how they would work.
Terrestrial sinks comprise plants and soilwhich prevent carbon dioxide from accumulating in the atmosphere by absorbing it in huge quantities (see box: Science of sinks). Increasing levels of a ghg like carbon dioxide in the atmosphere prevents the escape of solar energy into the outer space thus causing global warming. Over the past 150 yearsoceans and terrestrial ecosystems have absorbed 60 per cent of the carbon dioxide emissions caused by human activities.
The amount of carbon dioxide absorbed by terrestrial sinks can be increased or decreased through 'land useland use change and forestry' (lulucf) activities. 'Land use' refers to the sum total of activities undertaken on a certain land area. While this includes grazing and timber extraction that could release carbon trapped in terrestrial sinksit also encompasses conservation effortswhich could lead to increased carbon dioxide sequestration. The process of increasing carbon content of sinks is referred to as sequestration. Clearing forests for agricultural useconversion of grassland to croplandand abandoning cropland or pastureland qualify as 'land-use change' activities. From 1850 to 1998land use changeespecially deforestationled to an emission of approximately 33 per cent of the total 405 billion tonnes of carbon (gtc) into the atmosphere. 'Forestry'meanwhileincludes a wide range of activities like planting and tending of growing treespest controlfire managementwildlife protection and production of non-timber products.
Under articles 3.3 and 3.4 of the Kyoto Protocolcountries are allowed to engage in lulucf activities to sequester carbon dioxide from the atmosphere (see box: Articles of contention). Article 3.3 allows countries to resort to afforestationreforestation and deforestation (ard) activities to meet these commitments. Article 3.4 allows countries to get credits for enhancing carbon content in agricultural soil and by sequestering carbon dioxide through land use change and forestry (lucf) activities other than ard. This would include management of croplandgrazing land and forests.
The scientific uncertainties surrounding carbon sinks have been highlighted in a recent report by the Intergovernmental Panel on Climate Change (ipcc). "We know how to measure carbon in trees and soilbut we need a measurement system that is very densefrequent and complete" notes Robert T Watsonwho heads the ipcc panel. Moreoverthe effect of climate change on the sequestration potential of sinks is also uncertain. Scientists feel that with rising temperaturessinks may absorb lesser amounts of carbon dioxide (see box: Sinks turn sources).
To add to the problemlulucf activities may also be included under the Clean Development Mechanism (cdm)which is a project-based programme for trading credits between industrialised and developing countries. This will allow industrialised countries to claim credits towards reducing emissions by planting forests in developing countries thus making the most of their cheap land and labour (see box: Cheap deal).
The us-led group of countriesincluding JapanCanadaNew Zealand and Australiaare eager to include activities that enhance carbon dioxide absorption to fulfill their reduction commitmentsrather than reduce fossil fuel consumption. This is clearly because carbon dioxide mitigation through such activities is a cheaper option. The main controversy at The Hague meeting revolved around this group's demand for using activities like management of forestscropland and grazing land to get credits to meet Kyoto obligations. The eu and g77on the other handwant to exclude credits for such activities at least from the first commitment period (2008-2012)given the uncertainties.
Sinksin facthas been an issue of hot political and scientific debate since 1997when Australia pushed for its inclusion in the Kyoto Protocol. The 1990 emissions of carbon dioxide for Australia were high because of forest clearing activities. As they reduced their deforestation ratetotal emissions in 1996 decreased in comparison to 1990 levels. Australiathereforedemanded that their reduced emissions from land use change be included in calculating their baseline (1990) emissions. Non-government organisations (ngos) at Kyoto strongly opposed such a proposaldeclaring the issue of sinks to be a major loophole for countries committed to decrease emissions (see 'Kyoto's ghost will return'Down To EarthVol 6No 16 January 151998"While preparing the protocol we did not have the information provided by the ipcc (ipcc special report) on sinks" regrets Raul A Estrada Oyuelaone of the main architects of the Kyoto Protocoland currently Argentina's head of delegation to the climate negotiations. "Perhaps if we had more informationwe would have been able to develop things further. Three palm trees in one acre of land would not qualify as a forest."
Quagmire of definitions
So what should qualify as a forest? This is one of the main controversies that plagues the lulucf issue. Article 3.3 of the Kyoto Protocol can be implemented only after a consensus emerges among countries on the exact definition of a forest.
Most forest definitions are based on minimum canopy coverbut the ipcc report on lulucf says a common figure for canopy cover for forests in various regions is insufficient. If forest was defined as a mass of trees with a canopy cover ofsay 70 per centthen areas with sparse vegetation would not be considered forests. Thusthey could be cleared without any accounting for the resulting carbon dioxide emissions. Similarlya very low threshold ofsay 10 per centallows dense forests to be heavily degraded without the particular activity qualifying as deforestation.
Alternativelythe forest may be enhanced without the actions being considered as reforestation. The ipcc report suggests that biome-specific definitions be adoptedlike a low canopy cover for savannas and a high canopy cover for moist forests.
Reforestationmeanwhileis commonly defined asplanting of trees on land that has just been harvested. Heretoocontroversy arises if the definition of deforestation does not include harvesting. Then countries will be able to usethe amount of carbon dioxide sequestered arising out of regeneration towards fulfilling emission reduction commitments under the Kyoto Protocol. Howeverin such condi-tions corresponding emissions due to harvesting will go unaccounted for.
The implementation of article 3.4 requires accurate definitions for additional lucf activities apart from ardand activities that improve sequestration by agricultural soils. When an additional lucf activity is interpreted broadlythe net effect of all practicessuch as reduced tillage on land and irrigation in cropland management in a specific areaare considered to measure carbon content.
A narrow definitionon the other handmeans various practices undertaken on an area of land are taken individually to calculate the net change in the quantity of stored carbon. The way an activity is defined has implications in terms of separating naturally occurring changes from those due to human actions. A narrow definition will help in identifying the causes of decrease or increase in carbon content.
Direct or indirect?
A difficult condition attached to ard activities is that these should be 'direct' in nature. ipcc explains this by saying that the closer in time and space the activity is to the impactthe more direct it is. The reasons for engaging in a particular activity would also help in determining how direct it is.
'Indirect' effects includes climate change phenomenon like El Nio cyclesand carbon dioxide 'fertilisation' (where higher concentration of carbon dioxide in the atmosphere leads to plants absorbing more of it through photosynthesis). Such effects would significantly affect carbon dioxide sequestration during the commitment period of five years as prescribed by the protocol. Terrestrial ecosystems sequester an average of 2.2 gtc per year through natural regeneration and indirect effects. ipcc report warns that if countries are allowed to receive credits for even 50 per cent of sinks from these factorsthey would be able to meet their Kyoto commitments without lifting a finger.
Howevergiven the present availability of scientific toolsseparating direct effects from indirect ones will be very difficultif not impossible. Existing methods cannot precisely determine either the total or incremental amounts of carbon dioxide absorbed due to indirect effects like carbon dioxide fertilisation. At a project levelthis may only be possible when sequestration in a land area under the lulucf project is compared with a no project scenario.
Lulucf activities must also qualify as 'human induced'calling for yet another precise definition that distinguishes 'human induced' effects from natural effects. Factors such as natural cycles of disturbance and recovery from firespests and diseases could lead to significant changes over the five-year commitment period of the Kyoto Protocol. Sometimes these natural incidents may drive human decisions to undertake a lulucf activity. When a forest devastated by floodswith no scope for regenerationis converted into a croplandthe activity cannot necessarily be called human-induced --more so when emissions from these natural disturbances are not counted but the subsequent sequestration is considered. Equally confounding is that human actions may contribute towards natural occurrenceslike fires and pest infestations. Management practices may specify that certain fires be allowed to burn for ecological reasons.
Techniques are available to measure the changes in carbon contentbut attributing a given change to a particular cause is difficult. Even the most direct measurements on small areas cannot distinguish between intentional and natural causes for this change. Narrow definitions facilitate this separation of human induced activities from natural activities. Comparison between managed and unmanaged lands may help in quantifying changes that have occurred due to factors that are not naturalbut even this technique may be expensive when applied over large areas.
No permanent fix
Another problem with lulucf activities is that they tend not to be permanent. While reducing fossil fuel consumption provides a long-term solution to the problem of global warmingsequestered carbon dioxide can easily be released back to the atmosphere by firespestsencroachmentsor even climatic variations like drought or storms.
The ipcc report suggests that establishing projects in different areas may reduce damageas geographical separation would prevent firespests and diseases from spreading from one project area to another. Ensuring accounting of reductionseven if it happened due to natural reasonswill help in fixing liability on a country in case the project is disrupted. Projects may be assigned a minimum lifetime or limited credits may be issued. Howeversuch measures help only to a limited extent as the stored carbon may eventually be emitted.
An lulucf project may indirectly lead to carbon dioxide emissions outside the project's geographical limits. Since these emissions may not be taken into accountsuch spillover effects are called leaks. For instancea forest management activity that restricts the amount of land available for agricultural purposes or logging may compel local communities to clear forest elsewhere leading to emissions of carbon dioxide. It is necessary to include such emissionswhich do not fall within the confines of project areain calculations of changes in carbon dioxide levels. Howeverit is a daunting task to anticipate these impacts and attribute them to a particular project .
Cost versus uncertainty
Measuring changes in the quantity of carbon in plants and soils involves a compromise between precision and investment. To assess variations in stored carbonsample land areas are considered for this purpose. The greater the number of samplesthe more precise the estimate. Howeverthe more the number of samplesthe greater is the cost incurred by the countries undertaking the project.
Countries need to make substantial investment in human resourcestechnology and infrastructure to implement measurement methods. Additionallycarrying out such measurements on a regular basisas required by the protocolwill entail high operational expenses.
Most industrialised countries haveat leasta part of the infrastructurelike well-equipped laboratoriesaccurate maps for soil types and vegetationand trained personnelin place. Even then the incremental cost to perform these measurements regularly on a national scale may be substantial and taxing particularly for developing countries. For instanceAustralia is investing us $5 million annually to upgrade its existing system. Developing countrieswith lesser resourceswill be expected to establish similar systems when it is their turn to undertake emissions reductions.
These problems remain unresolved as the latest conference on climate change in The Hague failed miserably. Countries like JapanCanada and the us are also arguing in favour of lulucf activitiesas eligible options under cdm. Sequestration projects under this mechanism may have potential gains for local communities and developing countries but these gains can only be realised when associated difficulties are solved (see box: Handle with care and prudence). Most of them do not have proper infrastructure or reliable estimates of carbon levels in forests and soils.
It remains to be seen if climate negotiations scheduledfor May or June 2001 in BonnGermany will decisively resolve the loopholes associated with the Kyoto Protocol provisions on sinks.