Co-benefits of tackling poor air quality and regional and global climate: a focus on ecosystems

Kevin Hicks, Lisa Emberson, Patrick Büker, Johan Kuylenstierna and Mike Ashmore

CAPER, 16th April 2014, Lancaster, UK

kevin.hicks@york.ac.uk

• Global status of air pollution

• Drivers for policy

• Need for an integrated approach emphasizing co-benefits /multiple benefits of action

• Recent developments linking climate to clean air

• Outline research needed to inform decision making and protect our ecosystems

• Some implications for promoting policy uptake

Talk Outline

Sulphur emissions fall globally but not in Asia, and acidification is a potential concern

from UNEP GEO5, 2012

Oxidised and reduced nitrogen show different trends Global NHx emissions continue to rise

NOy emissions fall globally but increase in Asia

from UNEP GEO5, 2012

Future increases in ozone primarily in Asia rather than

Europe and North America

…but time course for concentrations of O3 and other pollutants will largely depend on when and how specific

control options are implemented

HTAP, 2010

Ozone is a hemispheric scale problem

HTAP, 2010

Air pollution is linked to a whole set of global drivers and policy challenges that include….

• Climate change

• Growth of population and consumption

• Urbanisation

• Food security

• Public health

• Loss of biodiversity and degrading ecosystem services

• Major political and social change

• Environmental justice

… and all of the challenges related to the global atmosphere are closely inter-linked; policy is moving towards more integrated approaches

from UNEP GEO5, 2012

Tropospheric Ozone (O3)

Direct effects leading to crop yield loss; forest

biomass loss and changes in species composition of

grasslands

Aerosols (nitrates, sulphates, black carbon etc...)

Indirect effects via acidification, eutrophication, and alteration to quality of incoming solar radiation

affecting photosynthesis

Linkages between air pollution, climate an ecosystems

warming warming & cooling

These pollutants are also radiative forcers and are often referred to as Short-lived climate pollutants (SLCPs)

Two key reports that brought political attention to SLCPs

Available at: http://www.unep.org/ccac/

Integrated Assessment of Black Carbon and

Tropospheric Ozone

‘Methane measures’

• extraction and long-distance transport of fossil fuels (~25%)

• waste management; municipal, landfills & wastewater (~10%)

• agriculture; livestock manure & intermittent rice aeration (~5%)

(% reduction in 2030 relative to reference)

IIASA ranked mitigation measures by the net GWP of their emission changes (considering CO, CH4, BC, OC, SO2, NOX, nmVOCs, and CO2),

picked the top measures

• Diesel vehicles (particle filters+)

• Coal briquettes replacing coal in residential stoves

• Pellet stoves & boilers replacing residential wood burning in industrialized countries

Black Carbon Measures

‘BC Measures’ that reduce emissions of black carbon and co-emissions (e.g. OC, CO)

• Clean-burning cookstoves in developing countries

• Modern brick kilns • Modern coke ovens

• Ban of open burning of agricultural waste

Effect of 16 measures on emissions projected in 2030 relative to 2005

9 BC measures reduce

80% of BC

Reference: CH4 increases 7 CH4 measures reduce 25% of CH4 (2005); or 40% relative to 2030

BC measures reduce

CO

This integrative approach has been applied, e.g. to assess the co-benefits of measures to reduce SLCPs

…but the methods used involved many empirical simplifications

Allows benefits of measures to reduce methane and black carbon emissions to be assessed in terms of climate, human health and

food security….but not a wider range of effects

This analysis can be linked to specific policy measures in different regions

Global crop yield loss avoided due methane measures

The share of global temperature reduction from methane measures

The share of total premature mortality avoided due to black carbon measures

The CCAC Leverage high-level engagement and political will, and catalyze action to

address SLCPs as a global and collective challenge to protect the environment and public health, promote food and energy security, and address

near term climate change Voluntary, Partner-led Coalition

• Feb 2012 -> 6 Partners • Feb 2014 -> 80 Partners: 36 States, IGOs, NGOs and private sector

Science driven, action-oriented Building on and bringing together existing efforts

Complementary to global efforts to reduce CO2 in particular under UNFCCC

National level: Fast start actions

Why national action?

• Most of health benefits related to air pollution reduction close to emission sources.

• Integrate measures with local sustainable development • Integrate measures with national climate policy.

Options for fast action

• Target obvious SLCP sources for immediate action • Consolidate actions in National Action Plan

Specific Action on Methane

• Near-term benefits will only be realised if specific action on methane is taken

N deposition is recognised as a threat to global biodiversity.. but only assessed in terms of critical threshold exceedance

Distribution of Nr deposition classes and exceedance of deposition levels in the period 2000-2030 on Protected Areas (PAs) under the Convention on Biological Diversity (Bleeker et al., 2011; UNEP, 2012).

Sutton et al. 2014

…different pollutants can cause a whole variety of different impacts on ecosystems, and the services ecosystems provide…

Ozone is also a threat to ecosystem services such as C sequestration

Same empirical approach applied across Europe

Very different results using concentration or dose Absolute reduction (Mt C) in C

storage in the living biomass of trees due to ozone applying AOT40

in (a) 2000 and (b) 2040, and PODY in (c) 2000 and (d) 2040, calculated from RCA input data

and applying the generic parameterisation in DO3SE (Y = 1 nmol m-2 PLA s-1) (Büker et al.,

2012).

Free Air experiments

Analytical modelling

Understand combined pollutant effects on key plant processes

CTMs

DGVMs

Develop new generation of Earth System Models

National/Regional/Global

CTM and DGVM modelling

experiments

(past, present and future)

Identify knowledge gaps

Controlled environment experiments

Des

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expe

rim

enta

l st

udie

s to

fill

kno

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gaps

To understand the effects of pollutants on ecosystems requires further development of our risk assessment tools….

…especially our Chemical Transport Models (CTMs) and Dynamic Global Vegetation models (DGVMs)

Conclusions - Science

• There is evidence that a variety of air pollutants are causing substantial damage to ecosystems around the globe…both by direct (toxic) and indirect (regional climate change) effects

• Current methods used to assess this pollutant damage to ecosystems concentrate on toxic effects of individual pollutants

• …but we know that pollutants interact and can, for example, cause greater toxic effects in combination

• …we also know that the pollutants cause a range of effects on ecosystems some of which ‘feedback’ and alter atmospheric composition

• A new means of capturing these multiple and integrated effects and feedbacks could be developing a new generation of ‘Earth System Models’ capable of assessing interactions and a variety of dynamic processes

Conclusions - Policy

• Need for more integrated climate change / air pollution policies to promote synergies and avoid trade-offs

• Clear Case for Action - linking the potential benefits to practical cost effective measures that can be taken on the ground is very attractive to policy makers and country governments

• Linkage to key policy drivers, especially human health effects, climate change, crop yields, water availability and attendant socio-economic benefits

• Voluntary as well as regulatory approaches important

• Transboundary dimension shows clear need for international cooperation

Translating the Science into Policy and Action

http://www.unep.org/ccac/

Further reading – out now!

http://link.springer.com/book/10.1007%2F978-94-007-7939-66

Thank you for your attention!