Title: Managing Urban Air Quality:
1Managing Urban Air Quality
- Questions for Policy Appraisal
The World Bank 14 May 2002
2Asking the Right Questions
- Questions posed can channel policy in a specific
direction - By limiting options for consideration from the
outset - By implicitly assuming a policy response as being
the best - Examples
- What is the contribution of geological matter to
SPM? - Control of road dust
- What are the surest technical options for
minimizing particulate emissions from heavy duty
diesels? - Advanced exhaust control or alternative fuels
3Question 1Is Outdoor Air Pollution Important?
- Is the impact of outdoor air pollution on public
health and lost productivity considerable
compared to other threats - Lack of access to safe drinking water
- Lack of adequate primary health care
- Malnutrition
- Extensive use of dirty fuels in households
- Yes pursue mitigation policies in urban air
pollution - No look for incremental policy opportunities in
- individual sectors
4Incremental Opportunities
- If damage from other sources (lack of clean
water, etc.) far exceeds damage from urban air
pollution, then - It is not cost-effective to mount large and
expensive government programs to combat urban air
pollution - But there are many cases where, at small
incremental cost, extending sector policies can
improve urban air quality - Example road widening in Hyderabad where the
entire road width is paved (no unpaved shoulders)
5Question 2Which Pollutants Should We Care About?
- Pollutants should be ranked according to
toxicity, ambient concentrations and exposure. - Fine particulate matter is the pollutant of
concern in India. - A common mistake is to rank on the basis of
emissions in weight based on an emissions
inventory. - Emission factors are uncertain or not available.
- Toxicity is not taken into account.
- Emissions in weight are not directly proportional
to ambient concentrations or exposure.
6Misuse of Emissions Inventory
- CO dominates total emissions in weight.
- CO is primarily from gasoline vehicles, and
transport is identified as the culprit. - Once transport is identified as the main
contributor, the focus shifts to black smoke. - Diesel vehicles are targeted as the highest
polluter, although the technical basis was CO
from gasoline vehicles.
7Question 3 What Is Causing Air Pollution?
- Need to identify sources contributing the most to
the general populations exposure to fine
particulate air pollution. - Large industrial plants.
- Small and medium size industries, diesel
generators. - Household consumption of solid fuels (biomass).
- Vehicular emissions.
- Leaf and informal refuse burning.
- Re-suspension of road-dust.
- Background and migration from other areas.
8How Much Do We Know About Sources of Particulate
Pollution?
- Little information on background particulate
concentrations ? if background level is high,
controlling human activities will be less
effective. - Measured data have large uncertainties ?
difficult to draw conclusions (e.g., correlation
between NO2 and PM10 to judge traffic
contribution). - Essentially no carbon analysis of particles.
- Very few quantitative source apportionment
studies. - ? Not much is known about relative importance of
different sources.
9Observations From Other Countries
- Mexico city three-fold PM10 variations, with
fugitive dust accounting for the differences. 50
of PM10, but only 15 of PM2.5, is geological. - UK road traffic contributes 25 of primary PM10
emissions, but 60 of PM0.1. Good correlation
between NOx and PM10. - USA even in California, gasoline cars can emit
as much as 1.5 g pm/km. A study in Colorado found
that gasoline PM emissions were grossly
under-estimated.
10Lessons for India
- Size of particles measured and examined drives
policy. - If PM10, difficult to lower if geological
contribution is substantial. - If sub-micron, efficient combustion processes
such as motor exhaust will increase in
importance. - Re-examine emission factors.
- Poor correlation between NO2 and PM10 in Delhi in
one study, but confirm data quality. - Need to quantify contributions from less studied
sources. - Chemical (especially carbon) analysis and
finger-printing. - Generating emission factors more suitable to
India.
11Question 4What Activities Do the Most Damage?
- For the sources identified as significant
contributors to the populations exposure to
small particles, which activities do the most
damage? - Examples
- Which vehicle and fuel combination in the
transport sector? - Which fuel and process combination in cottage
industries?
12Question 5What Policy Instruments Should Be
Used?
- Guiding principles.
- Recognize economic and financial constraints and
incentives, and work with, rather than against,
economic incentives as much as possible. - Better to have lax standards that are strictly
enforced, than strict standards that are not
enforced for the most part. - Different sectors have objectives that are not
necessarily compatible?recognize that there are
trade-offs.
13Considerations for Ranking Priorities
- Compatibility with other sector objectives
- Do they go against, or reinforce, other sector
objectives? - Cost of implementation
- Which measures would be the most cost-effective
(Rs / population exposure reduced)? - Ease of enforcement
- How difficult would it be to carry out the
proposed measures or to enforce them? - Political feasibility
- Are there strong vested interest groups that
would oppose the proposed measures vigorously?
14Policy Options
- Economic (differentiated) taxes, subsidies,
pricing (congestion, parking) - Administrative emission, energy efficiency and
fuel quality standards, restrictions on operation
(factories, vehicles, parking), protection of
non-polluting activities (NMT) - Technological fuel or technology mandates,
traffic management
15Linkages With Other Sectors
- Transport urban transport policy
- Municipal government municipal solid waste
management, policy towards slums - Welfare employment opportunities for the urban
poor - Urban planning zoning, densification
- Fiscal tax policy
- Energy supply and demand of oil and gas, power
16Which Pollutants Cause the Most Damage?
Is the impact of outdoor air pollution serious
compared to the impacts from other sources?
Fine PM
Does sector X contribute significantly to fine PM?
Which activities contribute significantly to fine
PM?
Which policy instruments will minimize
distortions and achieve results cost-effectively?