WMO CAS XV 18-25 November Seoul Korea 2009
August 2009 For Comment
Pre-CAS Public Web Consultation : Vision Paper (Agenda Item 8.2)
Posted 15 August 2009
Øystein Hov 1 , Jim Butler 2 and Greg Carmichael 3
The changes in air pollution, climate and the biogeochemical cycles of trace chemicals in the atmosphere such as carbon and reactive nitrogen give rise to environmental problems.
Meteorological processes often strongly influence their severity and rate of change. The analysis and abatement of these problems require an interdisciplinary approach both nationally and internationally. WMO and its member countries should intensify the effort to develop appropriate partnerships across disciplines nationally and internationally to address these challenges. It is important now to develop a common understanding of air pollution, its health impact, its long range transmission and the interaction with climate change. Many international conventions and initiatives would benefit greatly from a common approach developed with the help of WMO and its partners nationally and internationally. These include: the WMO co-sponsored Intergovernmental
Panel on Climate Change (IPCC), the United Nations Framework Convention on Climate Change
(UNFCCC), the WMO-UNEP supported Vienna Convention on Protection of the Ozone Layer, the
Reactive Nitrogen Initiative, the Global Earth Observation System of Systems (GEOSS) and its
European component Global Monitoring for Environment and Security (GMES), the Convention for the Long Range Transmission of Air Pollutants (CLRTAP) and the Malé declaration (see references at the end of the paper).
WMO should play a leading role in strengthening the observing systems needed to support air quality prediction at multiple scales. Near-real time delivery of environmental data is an important component of forecasting urban pollution. Both the near-real time delivery of urban observations and the forecasting activity should be pursued at the national or local levels. WMO should continue to provide advice and capacity building.
WMO should lead a global partnership to link together globally the technical work on the regional/continental long range transport of air pollution. This includes the delivery of environmental data to allow both for day-to-day assessment of the long (and very long) range transport of air pollution; hindcast analysis and scenario calculations. Near-real time delivery of pollution related observations and the forecasting of pollution should be pursued at the international, national and local levels depending on the issue at hand.
Managing and integrating global greenhouse gas observations and analyses are long-held capabilities of the WMO through the Global Atmospheric Watch programme that is recognized as the comprehensive network of the Global Climate Observing System (GCOS). Providing reliable, quantitative information routinely to groups striving to reduce carbon dioxide emissions requires information from a globally coordinated network. International coordination by WMO can provide a better basis for a global carbon tracking system sustained by monitoring of greenhouse gases, aerosols and reactive gases such as tropospheric ozone, and the provision of services derived from these observations.
The cycling of reactive nitrogen between the atmosphere, fresh water systems, terrestrial ecosystems and the oceans influence several issues of high relevance to WMO and its member countries. Two examples are the quality of the water supply and the link between the reactive
1 Norwegian Meteorological Institute
2 NOAA ESRL
3 University of Iowa, USA
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WMO CAS XV 18-25 November Seoul Korea 2009
August 2009 For Comment
Pre-CAS Public Web Consultation : Vision Paper (Agenda Item 8.2)
Posted 15 August 2009 nitrogen cycle, air pollution and climate forcing and feedbacks. WMO should actively support the analysis of the reactive nitrogen cycle with a view to advise and build capacity among its member states in order to minimize reactive nitrogen loss to waterways and to the atmosphere, while the use of reactive nitrogen fertilizer is enhanced in regions where food production is nitrogen deficient.
WMO is best placed internationally to take the lead in the technical analysis of how climate variability and change and air pollution interact both ways on a regional basis, and in combination on a global basis, as these are issues of immediate concern throughout the world affecting societies to an extent that is not well known but could be significant (air pollution events, floods, droughts; water supply, food supply etc). These issues are discussed in more detail in the rest of this paper.
Air pollution in, around and downwind of megacities affects human health in important ways throughout the world. The forecasting of urban to regional scale air pollution is an important service in order to allow the population to take precautions to reduce risk to health on a daily basis and to identify policy measures to reduce pollutant inputs to the atmosphere so that air quality objectives and standards set to protect society can be met. Air quality and related issues depend strongly on the meteorological conditions that effect dispersion and emissions (e.g., wind blown soil fluxes depend on surface winds and evaporative emissions depend on temperature). Thus, a better characterization of meteorological conditions has direct benefits to air quality prediction and management.
There are some important differences in the spatial and temporal requirements for air quality and meteorological observations in urban and surrounding regions. Severe air pollution problems are often associated with stagnant weather conditions, and with phenomena such as urban heat islands, nocturnal jets and local circulations like sea-land breezes, which have not been the primary focus of observing systems nor numerical weather prediction efforts. Boundary layer information such as mixing layer height and clouds, is of particular importance. Key meteorological parameters for air quality applications include temperature, wind speed and direction, boundary layer characterization, relative humidity, solar radiation, and with a horizontal resolution as fine as less than a kilometer (i.e. city block scale).
There is growing attention directed at the global reach and impact of air pollution (TFHTAP, 2007).
Addressing this concern requires the capability to observe and predict air quality at scales from local to regional to global. The coupling of hemispheric, regional and local air pollution needs further investigation to determine the extent to which population exposure to air pollution is of transboundary origin as well as to identify sets of measures to control such exposure. The coupling of geographical scales also determines the concentration of particulate matter for which further physical and chemical characterization is important for the calculation of dispersion and to assess the human health effects, which must be assessed in consultation with World Health Organization
(WHO) and other active organizations. Mesoscale circulation can be an important cause of high unexpected exposure of a population to air pollution. An example is the cycling of air in and around a sea basin like the Mediterranean Ocean and its role in determining the air pollution load along the South European Mediterranean coast.
Borrowing lessons learned from the evolution of numerical weather prediction (NWP) models, improving air quality predictions through the assimilation of chemical data holds significant promise. Careful design and use of observations is needed to produce an expanded capability in air quality prediction. In addition the benefits to weather prediction due to the assimilation of chemical measurements may be significant, but have not yet been evaluated.
There remain major deficiencies in our meteorological observing system in support of air quality
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WMO CAS XV 18-25 November Seoul Korea 2009
August 2009 For Comment
Pre-CAS Public Web Consultation : Vision Paper (Agenda Item 8.2)
Posted 15 August 2009 prediction; the major short comings are related to measurements aloft, in urban environments, over water and in temporal resolution. Furthermore the observing system for air pollutants to support air quality prediction at multiple scales is in its infancy. The following are critical needs in air quality risk reduction: i. Expansion of the geographical coverage of air quality measurements, ii. Extending surface-based (in situ and remote sensing) and aircraft measurements above the surface (lowest few km) to provide critical information not well provided by satellite observations, iii. Adding a near real time access to the observations,
WMO enhances through the GAW Urban Research Meteorology and Environment (GURME) project the capabilities of the member states to provide air quality forecasting, illustrating the linkages between meteorology and air quality. WMO facilitates easy access to information on measurements, modelling and assimilation techniques. WMO promotes pilot projects to demonstrate how member states can expand their activities into urban environment issues; and
WMO works with WHO and environmental agencies to better define meteorological and air quality measurements that support urban forecasting.
WMO should play a leading role in strengthening the observing systems needed to support air quality prediction at multiple scales. Near-real time delivery of environmental data is an important component of forecasting urban pollution. Both the near-real time delivery of urban observations and the forecasting activity should be pursued at the national or local levels. WMO should continue to provide advice and capacity building.
On a regional or continental scale the main air pollution problems are related to elevated surface ozone, particulate matter (determined by chemical composition and physical characteristics), acid deposition, deposition of nutrients (eutrophication) and the deposition of heavy metals and persistent organic pollutants.
The economy is globalised with important consequences for the change in abundance of intercontinental transport of air pollution. The emissions of gaseous precursors of particulate matter and oxidants in the atmosphere are growing in the Far East and in South America, while emissions in Europe and North America are levelling off or being reduced. Aircraft emissions and shipping emissions are growing. Changes in farmland practices and in physical climate give rise to more biomass burning, forest fires and sand and dust storms. Increasing attention is needed to understand the intercontinental transport of air pollution and its contribution to the pollution levels in various regions (including Europe, the Arctic, marginal seas, etc.).
The organisation of the investigation of regional to continental scale transboundary air pollution needs to be linked together globally through a common technical framework. There are several existing regional mechanisms such as the European Monitoring and Evaluation Programme of the
CLRTAP in Europe, EANET in the far East, the Malé Declaration on “Control and Prevention of Air
Pollution and Its Likely Transboundary Effects for South Asia ”. The WMO Global Atmosphere
Watch programme ( http://www.wmo.int/gaw ) is one proven international mechanism for coordination that can play a lead role. Also emerging as a useful global framework is the WMO
Sand and Dust Storm Warning Advisory and Assessment System (SDS-WAS;
( http://www.wmo.int/sdswas ).
WMO could assume the lead in linking together technical work on the regional/continental long range transport of air pollution globally. This includes the near real-time delivery of environmental
3

WMO CAS XV 18-25 November Seoul Korea 2009
August 2009 For Comment
Pre-CAS Public Web Consultation : Vision Paper (Agenda Item 8.2)
Posted 15 August 2009 data to enhance accuracy of weather forecasts and to allow for day-to-day assessment of the long
(and very long) range transport of air pollution; hindcast analysis and scenario calculations.
UNFCCC is a convention dedicated to mitigating and adapting to climate change effect of long lived greenhouse gases. Ozone and particulate matter including aerosol pollution, black carbon and sand and dust are atmospheric constituents that have very short atmospheric residence times compared to greenhouse gases yet the direct and indirect radiative forcing of tropospheric ozone and particulate matter is a significant fraction of global radiative forcing. Controls of emission of these short-lived substances will have an immediate effect on radiative forcing while we must wait much longer for greenhouse gas controls to have a mitigating impact. In addition the regional radiative forcing of climate due to particulate matter and tropospheric ozone is expected to modify weather patterns and possibly the frequency and intensity of storms. The extent of the modification and its societal impact is not well known, but could be important.
Climate variability and change have consequences for atmospheric composition through the modification of temperature, surface properties (drought and plant cover), cloud cover, precipitation including length of dry periods, boundary layer mixing properties etc. The adaptation of societies to climate change has consequences for atmospheric composition for instance through changes in the emissions from energy consumption as the energy production system moves towards more extensive inclusion of renewable energies including biofuels.
To properly account for the coupling of dynamics, physics and chemistry and the cycling of biogeochemical tracers between the soil, the atmosphere and the oceans, chemical transport models need to be integral parts of weather or climate models that in turn are moving toward full
Earth System Models (ESMs) as appropriate (report of WMO Executive Council Research Task
Team; http://www.wmo.int/ecrtt ). Quantification is needed of fluxes of trace chemical species between terrestrial ecosystems and the atmosphere, and between the oceans and the atmosphere
(focus on fluxes rather than concentrations). The interaction between the hydrological cycle and biogeochemical cycles determines the indirect effect of atmospheric water vapour and cloud water, and determines the removal and deposition pattern of water soluble chemical trace species including particles.
WMO should take the lead in the technical analysis of how weather and climate variability or change interact both ways with air pollution on a regional and global basis. This is an issue of immediate concern throughout the world affecting societies to an extent that is not well known but could be significant (air pollution events, storms, floods, droughts, water supply, food supply etc)
2
Unless mitigation actions are taken, CO
2
emitted into the atmosphere will remain there for a very long time – 100’s to 1000’s of years, during which it will continue to warm the earth and acidify the oceans. Other greenhouse gases, with very long atmospheric lifetimes, are increasing in the atmosphere as well, in large part due to human activities. The combined effect of these continued emissions has already led to warming and certain climate change impacts.
A substantial strengthening of efforts to reduce CO
2
emissions will probably happen sooner rather than later. Unlike other large-scale emission reduction efforts (e.g. ozone-depleting compounds, controls on sulphur and nitrogen oxide emissions related to acid rain and human health), these will involve many economic sectors of society and will vary by nation, region, and approach. Largescale emission reductions in the past have all required on-going verification to ensure that the
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WMO CAS XV 18-25 November Seoul Korea 2009
August 2009 For Comment
Pre-CAS Public Web Consultation : Vision Paper (Agenda Item 8.2)
Posted 15 August 2009 desired outcomes are achieved. These include measurement of pH in lakes and rain for sulphur emission reduction; atmospheric measurements of ozone and ozone-depleting gases for stratospheric ozone recovery; atmospheric measurements of ozone, other reactive gases and particulate matter for regional air quality policies. The complexity and variability of the carbon cycle, the involvement of other GHGs, the global nature of the problem, and the number and variety of emitters and offset options, however, make independent verification of greenhouse gas management strategies a challenging task, but one that must be done.
The ability of nations to implement policies that effectively limit atmospheric GHG concentrations will depend upon their ability to monitor their progress and determine what is and is not working.
While current uncertainties in existing data sources are perhaps acceptable for current policy purposes, they need to be reduced substantially for effective policies on climate mitigation.
Current efforts to monitor and limit GHG emissions are mostly based on land-use observations, self-reported data on energy use, and other economic activities. While such data may be sufficient for today, they are known to have many uncertainties that limit their ability to support implementation of GHG-management related to climate. This presents a challenge to implementing a range of GHG policies that are discussed in many countries, including supporting treaty negotiations, verifying treaty obligations, certifying tradable permits, offsetting GHG emissions, and providing a more accurate inventory of emitters. Add to this the complexity and variability of the natural carbon cycle and the effects of climate change on natural systems that exchange CO
2
and other GHGs (e.g., N
2
O, CH
4
). Thus to develop effective GHG management strategies, there is an urgent need for a globally integrated observation and analysis system to track changes in atmospheric GHGs and provide routine estimates (with confidence limits) of net atmospheresurface exchange on a regional or sub-regional basis
WMO, through its Global Atmospheric Watch (GAW) programme, has long provided a framework for global greenhouse gas monitoring and integration of those measurements, and it is recognized by UNFCCC and the Global Climate Observing System as the lead international framework. It includes facilities and observations managed by national partners linked together by GAW.
Components of this system include a Central Calibration Laboratory for the World Reference
Standard for Greenhouse Gases, the World Data Centre for Greenhouse Gases; WMO sponsored biennial e xperts’ meetings on CO
2
, other greenhouse gases, and related tracers; the quadrennial
International Carbon Dioxide Scientific Conference and other relevant conferences, workshops, and meetings. GAW also promotes reanalysis to develop informational products; provides training opportunities to help build capacity in contributing to the observational system; and the development strategies for integrating land, ocean, and atmospheric observations to understand the role of the Earth system in greenhouse gas management.
WMO should implement the following recommendation (#5 of the 2008 CAS Management Group
Meeting):
“WMO should work towards establishing an integrated, Global Carbon Observation, Prediction and
Assessment System, acknowledging that monitoring requirements may be forthcoming to support global emission reduction and mitigation policy, and recognizing that CO
2
interacts strongly with the biosphere and hydrosphere, that considerable research is necessary to support such a system, and that such research will need to be compatible with what might ultimately become operational – that is, aiming at operational implementation: a. Integrating and expanding existing observing systems and validating and incorporating satellite and aircraft measurements to produce a global, near real time database of atmospheric CO
2
; b. Developing and implementing an ensemble based reanalysis for research and operational applications that includes surface atmosphere interactions; and c. applying model-based systems to analysis and prediction of the transport and evolution of
CO
2
. These systems should be linked to operational frameworks to insure reliable access to
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WMO CAS XV 18-25 November Seoul Korea 2009
August 2009 For Comment
Pre-CAS Public Web Consultation : Vision Paper (Agenda Item 8.2) data, production of forecasts, and delivery of services.
”
Posted 15 August 2009
Humans continue to transform the global nitrogen cycle on Earth at a record pace, reflecting an increased combustion of fossil fuels, growing demand for nitrogen in agriculture and industry, and pervasive inefficiencies in its use. Much anthropogenic nitrogen is lost to air, water, and land causing a cascade of environmental and human health problems. Simultaneously, food production in some parts of the world is nitrogen-deficient, highlighting inequities in the distribution of nitrogen containing fertilizers. Optimizing the need for a key human resource while minimizing its negative consequences requires an integrated interdisciplinary approach and the development of strategies to decrease nitrogen-containing waste (quote from Galloway et al., 2008).
Reactive nitrogen influences eutrophication of water bodies, atmospheric oxidative capacity
(through the hydroxyl radical, ozone and the nitrate radical) which affects atmospheric residence times of some greenhouse gases such as methane and the composition of atmospheric particulate matter.
The atmospheric component of the biogeochemical cycle of reactive nitrogen including its relation to the sequestration of carbon in ecosystems, is not well known. Reactive nitrogen cascades through environmental compartments with approximately 165 Mt-N of reactive nitrogen produced each year, of which about 75% is related in some way to agriculture and 25% to the combustion of fossil fuels and the industrial use of nitrogen.
The technical assessment work on reactive nitrogen takes place in the International Nitrogen
Initiative ( http://www.iniforum.org/ ) and through European initiatives on reactive nitrogen. These are focused on a scientific understanding of the use and release of reactive nitrogen and development of measures to improve its management (European Science Foundation’s (ESF) projects Nitrogen in Europe (NinE) and COST 729 as well as EU research projects).
The cycling of reactive nitrogen between the atmosphere, fresh water systems, terrestrial ecosystems and the oceans influence several issues of high relevance to WMO and its partners worldwide. WMO and its member countries could take a lead in the global coordination, particularly with respect to is feedback on climate forcing . This has implications locally or regionally; for example, on the quality of the water supply and the link between the reactive nitrogen cycle, air pollution and climate change. WMO should actively support the analysis of the reactive nitrogen cycle with the view to advise and build capacity among its members to minimize reactive nitrogen loss to waterways and to the atmosphere, as well as advise on how to augment the use of reactive nitrogen fertilizer in regions where food production is nitrogen deficient.
In the past WMO led or was a major co-sponsor of a series of scientific assessments that laid the groundwork to establishment of the CLRTAP and the Vienna Convention on Protection of the
Ozone Layer. Changes in air pollution, climate and the biogeochemical cycles of trace chemicals like carbon and reactive nitrogen give rise to new environmental problems that require internationally coordinated action. The scientific analysis and mitigation strategies for these problems require an interdisciplinary approach both nationally and internationally. WMO and its partners worldwide are well placed to lead a cooperative effort to develop appropriate partnerships across disciplines nationally and internationally to address these challenges. Many international conventions and initiatives would benefit greatly from a common approach developed with the help of WMO and its partners nationally and internationally. These include: the WMO co-sponsored
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WMO CAS XV 18-25 November Seoul Korea 2009
August 2009 For Comment
Pre-CAS Public Web Consultation : Vision Paper (Agenda Item 8.2)
Posted 15 August 2009
Intergovernmental Panel on Climate Change (IPCC), the WMO-UNEP supported United Nations
Framework Convention on Climate Change (UNFCCC), the Vienna Convention on Protection of the Ozone Layer, the Reactive Nitrogen Initiative, the Global Earth Observation System of Systems
(GEOSS) and its European component Global Monitoring for Environment and Security (GMES), the Co nvention for the Long Range Transmission of Air Pollutants (CLRTAP) and the Malé declaration (see references at the end of the paper).
WMO can provide advice and capacity building, while near-real time delivery of pollution-related observations and the forecasting of pollution should be pursued at the international, national and local levels depending on the issue at hand. International coordination by WMO can also provide a better basis for a global carbon tracking system sustained by monitoring of greenhouse gases, aerosols and reactive gases such as tropospheric ozone, and the provision of services derived from these observations.
CLRTAP ( http://www.unece.org/env/lrtap/welcome.html
),
EANET ( http://www.eanet.cc/ ), Acid Deposition Monitoring Network in East Asia
EMEP strategic plan 2010-2019 (2009) http://www.unece.org/env/documents/2009/EB/ge1/ece.eb.air.ge.1.2009.10.e.pdf
Executive Council Research Task Team WMO (2009) Challenges and opportunities in research to enable improved products and new services in climate, weather, water and environment. A Report of the Executive Council Task Team (EC-RTT) on Research Aspects of an Enhanced Climate,
Weather, Water and Environmental Prediction Framework. http://www.wmo.int/ecrtt
Galloway, J.N., A. R. Townsend, J. W. Erisman, M. Bekunda, Zucong Cai, J. R. Freney, L. A.
Martinelli, S. P. Seitzinger and M. A. Sutton (2009) Transformation of the Nitrogen Cycle:
Recent Trends, Questions, and Potential Solutions. Science 320, 889-892.
GAW Strategic Plan 2008-2015. ftp://ftp.wmo.int/Documents/PublicWeb/arep/gaw/gaw172-
26sept07.pdf
Levin, Z. and W. R. Cotton (Eds.) (2009) Aerosol Pollution Impact on Precipitation. A Scientific
Review. 386 p. Springer. ISBN: 978-1-4020-8689-2.
Malé declaration ( http://www.rrcap.unep.org/male/baseline/indexpak.html
)
Managing the European Nitrogen Problem (2009) www.clrtap-tfrn.org/european-research-strategy
Reactive Nitrogen Initiative ( http://www.iniforum.org/ ),
TFHTAP (2007) Interim report prepared by the Task Force on Hemispheric Transport of Air
Pollution (TFHTAP) acting within the framework of the Convention on Long-range Transboundary
Air Pollution (CLRTAP) http://www.htap.org/assessment/2007_interim_report/HTAP%202007%20EB%20version.pdf
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