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Massachusetts Institute of Technology
Departnnent of Economics
Working Paper Series
WINTER HEATING OR CLEAN AIR?
UNINTENDED IMPACTS OF CHINA'S HUAI RIVER POLICY.
Douglas Almond
Yuyu Chen
Michael Greenstone
Hongbin
Li
Working Paper 09-02
January 9, 2009
Room
E52-251
50 Memorial Drive
Cambridge,
MA 021 42
This paper can be downloaded without charge from the
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http://www.archive.org/details/winterheatingorcOOalmo
Winter Heating or Clean Air? Unintended Impacts of China's Huai River Policy*
Douglas Almond
Columbia University and
NBER
Yuyu Chen
Guanghua School of Management
Michael Greenstone
MIT, NBER, and Brookings
Institution
Hongbin Li
Tsinghua University
January 2009
*
We
thank Matthew Neidell for his insightful discussion
at
the
2009
AEA
Meetings,
Faibushevich, Haitao Ruan, and Henry Swift provided outstanding research assistance.
thanks the US-China Fulbright Program for financial support.
llya
Almond
Winter Heating or Clean Air? Unintended Impacts of China's Huai River Policy
ABSTRACT
This paper assesses the role of heating entitlements
in
generating stark
air quality differences
across China. During the 1950-1980 central planning period, the Chinese government established
free winter heating of homes and offices as a basic right via the provision of free coal fuel for
boilers.
The combustion of
coal
in
boilers
especially total suspended particulates (TSP).
entitlement
was only extended
Qinling Mountains
TSP
in central
in a
in a
to
to areas to the north
We
China.
levels in the north; the difference
This result holds both
associated with the release of air pollutants,
is
Due
is
budgetary limitations, however, this heating
of the
line
formed by the Huai River and
find this procrustean policy led to dramatically higher
roughly 5-8 times current
TSP
concentrations
panel data setting that compares the marginal effect of winter temperature on
and southern China.
in the
In contrast,
we
fail to
TSP
find evidence that the heating policy has a
in
Douglas Almond
Department of Economics and SIPA
Columbia University
420 West 18th Street, MC 3308
New York, NY 10027
1
Yuyu Chen
Applied Economics Department
Guanghua School oof Management
Peking University
Beijing. 100871
andNBER
CHINA
Phone:212-854-7248
Fax:212-854-8059
Email: chenyuyu@gsm.pku.edu.cn
Phone:0086-10-62757902
Email: da2152(a)columbia.edu
Michael Greenstone
MIT, Department of Economics
50 Memorial Drive, E52-359
Cambridge, MA 02142
and Brookings Institution and
NBER
northern
meaningful
impact on sulfur dioxide (SO2) and nitrogen oxide (NOx) concentrations.
Phone:617-452-4127
Fax:617-253-1330
Email: mgreenst@mit.edu
US.
cross-sectional regression discontinuity-style estimation approach and
Hongbin Li
Department of Economics
School of Economics and Management
Tsinghua University
Beijing 10084
CHINA
Phone: 86-10-62792924
Fax: 86-10-62785562
Email: lihong,bin(a)sem. tsinghua. edu.cn
Air quality
Particulates
China
in
is
Ambient concentrations of Total Suspended
notoriously poor.
(TSP) 1981-1993 were more than double China's National Annual Mean Ambient Air
Quality Standard of 200 mg/m"^ (Xiaohui Bi
et al.,
2007) and five times the level that prevailed
the U.S. before passage of the Clean Air Act in 1970.
quality
is
especially poor in northern Chinese cites.
southern city of Shanghai, Prime Minister
[in
Further,
northern China],
I
would shorten
my
it
air
quality
within
Zhu Rongi quipped
life at least five
in
1999: "If
government established
free winter heating
TSP. Due
to
areas located in northern China.
your Beijing
years" {The Economist, 2004, pp. 55-57).
in boilers is
in
generating stark differences
associated with the release of air
budgetary limitations, however,
The
in
the
of homes and offices as a basic right via the provision
of free coal fuel for boilers. The combustion of coal
pollutants, especially
work
I
in
1950-1980 central planning period, the Chinese
During the
China.
frequently claimed that air
For example, following a career
This paper assesses the role of a procrustean Chinese policy
in
is
in
line
this right
was only extended
to
formed by the Huai River and Qinling Mountains
denotes the border between northern and southern China.
Matching
air pollution
led to dramatically higher
and weather data for 58 Chinese
TSP
levels in the north.
all
permanent
Chinese
city-level determinants
cities.
In contrast,
we
of
fail to
sulfur dioxide (SO2) and nitrogen oxide
I.
TSP
TSP
in
we
find the heating policy
This result holds both
regression discontinuity-style estimation approach and
marginal effect of winter temperature on
cities,
in a
in
a cross-sectional
panel data setting that compares the
northern and southern China, after controlling for
concentrations and transitory ones
common
to all
find evidence that the heating policy leads to increases in
(NOx) concentrations.
Brief Background on China's Heating System and Huai River Policy
China's heating system was established during the three decades of the planned regime,
1950-1980.
heating for
In this period,
homes and
heating
was considered a
offices, either directly or
through state-owned enterprises.
heating did not arrive in China until the mid-1990s,
system remains today as
Due
to
many homes and
The legacy of this
offices continue to receive free heat.
The average January temperature
is
is
defined by
roughly 0° Celsius
line.
Northern Chinese
In
after the analysis period.
The border between northern and southern China
the Huai River and Qinling Mountains.
15.
i.e.
Commercial
budgetary limitations, the Chinese government limited the heating entitlement to
areas located in northern China.
along this
basic right and the government provided free
cities
was (and
heating
contrast,
government did not supply
November
just south
of the Huai River,
like
15 and
March
remains) non-existent lo the south because the
was
there a private sector to supply
widely recognized that winters are cold and uncomfortable
Indeed,
is
largely
a heating infrastructure, nor
recently.
it
received free unlimited heating between
it
until
in cities that are
Nanjing, Shanghai, and Chengdu.
The Chinese heating system
is
coal-based and technically inefficient. Most heat was and
is
provided by coal-fired heat-only boilers or combined heat and power generators, which are
inefficient in
(T.J.
Wang
energy usage compared to
et al.,
electric,
gas and
oil
heating systems
in
industrial countries
for a residential building, heat typically comes from a
2000; Yi Jiang, 2007).
boiler in the building or a separate heating factory; in either case, boilers burn coal to heat water
which
is
sent through iron pipes to each household.
In the latter case,
travels long distances before reaching a household, during
The incomplete combustion of
measured types of
air pollution.
There
which there
is
heated water frequently
substantial energy loss.
coal in these boilers leads to the release of at least three
is
little
doubt that
this
causes substantial
TSP
emissions.
SO2 and NOx. The amounts of these
All coal combustion also produces
with the kind of coal used, which
data on this).
is
responsible for
87%
we were
geographically (although
in turn varies
Estimates from the mid-1990s suggest that
coal combustion
pollutants produced vary
76%
and
industrial
all (i.e.,
NO^
of SO2 and
unable to obtain
and non-industrial)
emissions, respectively
(National Research Council. 2004).
This paper's central task
to
is
provide the
NO^
China's Huai River Policy on TSP. SO2 and
First,
we
test
whether concentrations are higher
adjustment for a polynomial
that has
become
This
in latitude.
increasingly popular
first
in
concentrations.'
northern
whether concentrations are higher
in
is
done
in
two ways.
southern ones, after
cities, relative to
(Thomas D. Cook and Donald
1979; Michael Greenstone and Justin Gallagher. 2008; Douglas
test
This
approach
test is similar to a regression discontinuity
recent years
in
systematic documentation of the impacts of
northern
Almond
et al.,
cities, relative to their
T. Campbell,
2008). Second,
we
long run average, after
This approach takes advantage of the substantial
adjustment for the realized temperature
in year.
inter-annual variation in temperature to
compare the impact of changes
in
temperature on ambient
pollution concentrations in north and south China.
II.
Data Sources and Descriptive
This paper utilizes two primary data
sets.
The
annual daily average concentrations of TSP. SO2. and
file is
unbalanced and a
total
of 76
cities
Statistics
first is a
NOx
'
There
is
some evidence
that this heating
Shuxian Fan
et al.
have a recorded concentration for
pohcy leads
(2004) show that
winter than during the rest of the year.
in
site
Yinchuan,
In the capital city
much lower
reports
at least
and are part of
one pollutant
its
in
"Economics
to substantial increases in pollution concentrations during the
TSP
concentrations are significantly higher in the
of Xinjiang, Wulumuqi,
are emitted from the heating system (Tianshan, 2006). Jinliuan Qiu and Liquan
northern cities in winter was
file that
during the period 1981-1993. The data
one year. The data were downloaded from a World Bank web
winter months.
city-by-year data
90%
of the pollutants
Yang (2000)
in
the winter
find that visibility in five
than during the rest of the year between 1980 and 1994.
of Pollution Control Research" project.
The World Bank compiled
the
1981-1990 data from the
China Environmental Quality Report, produced by the China National Environmental Monitoring
Station, dated July, 1991;.the
1991-1995 data come from the China Environment Yearbooks from
China's State Environmental Protection Administration.
The second data
triplet.
was
It
file
is
the average daily temperature reported for each year-month-city
collected from the China Meteorological Administration and covers the years 1981-
1993, so our analysis will be limited to these years.
We
calculate a city's winter temperature
given year as the simple average of the December through February mean temperatures.
cities
we
can match pollution and weather data for
Figure
Mountains
at least
line is the
dark line
the dividing line ranges
in the figure that
divides China into
between 33.03° and 34.25°
In
58
one year.
The Huai River/Qinling
displays the location of each city in our analysis.
1
in a
latitude,
no
its
north and south.
cities in
Although
our analysis sample are
located in this interval.
Table
air
1
1998.
summary
cities
some key
variables.
Further, the standard deviation of the annual city-specific
China's mean
five limes
US
(
TSP
TSP
of
among
concentration
means ranged between
concentrations over the 1981-1993 period were 538
levels prior to the successful Clean Air Act!
mg/m^ The mean SO2
13
(1992
mg/m
,
more than
Further, the standard deviation of the
concentration
in the
China data
is
109
TSP data that the authors obtained by filing a Freedom of
Kenneth Chay and Michael Greenstone, 2003a, b, and 2005 for further
These papers also provide evidence on the success of the US Clean Air act on reducing TSP
calculations are derived from monitor-level
Information Act request with the
data details).
striking are the levels
1970).^
annual city-level means was 330
The U.S. TSP
Most
ranged between 100 mg/m^ (1964) and 42 mg/m^ (1993) during the years 1964-
and 1993) and 61 mg/m'
^
statistics for
For comparison, the average U.S.
concentrations.
pollution
monitored
reports
concentrations.
EPA
(see
mg/m which
,
is
substantially greater than the 1990 U.S. average of 23
concentrations are more similar: 40.5
reflect the relatively
It is
mg/m^
U.S. versus 56.5
in the
low levels of motor vehicle usage
in
mg/m^
China during
in
China, which
may
this period.
evident that China provides an unique opportunity to study the impacts of air pollution
concentrations on willingness to pay for clean air and
exceeding those ever recorded
a key ingredient
is
mg/m^ The NOx
in
exogenous variation
in the
human
U.S. or other any other country. The availability of this data
any such study, but equally important
The remainder of
in air pollution.
River policy provides variation
health at pollution levels far
in air pollution at
III.
is
the identification of plausibly
the paper explores whether China's Huai
these extraordinary concentrations.
Econometric Strategy
This section describes the two econometric models used to examine the impact of the Huai
River policy on
(
1
)
TSPa = a + pi (North) ^ + n
where c references a
concentration
outcome
between
is
by year.
etc.).
and
+
indexes a year.
(We
|at
is:
+
£ci,
The dependent
also estimate
models
for
variable
is
the average daily
SO2 and NOx
the city lies above or
northern
air pollution
concentrations
(e.g.,
due
to
concentrations.)
TSP
The
temperature, topography, hours
Additionally, the model includes year fixed effects,
in the
The parameter of
in
/
f{Latilnde)^
1
adjusted for a polynomial of degrees latitude, which adjusts for any association
of the business cycle
higher
and
city
in a city
this variable
of daylight,
Model
air pollution concentrations.
//,,
to capture the influence
unbalanced panel.
interest
is /?,
the coefficient on the indicator variable UNorthJc'. whether
below the Huai River
cities, after flexibly
line.
It
assesses whether pollution concentrations are
adjusting for their latitude and the year fixed effects.
To
the
extent
unobserved determinants of
that
(permanent or transitory) change discretely
impact obtained from Model
Therefore,
TSPa =
(2)
we
1
at the
concentrations
pollution
air
Huai River
northern
in
cities
estimates of the heating policy's
line,
will be biased.
also estimate the following equation,
which we
a+ p
Winter Temperature ^ + ^- [Winter Temperature
+ 6, + ^, + Cct
.,.^
refer to as
^i
Model
2:
x IfNorthJcJ
^
This equation adjusts for the realized winter temperature and city fixed effects,
pollution concentrations across cities, and thereby addresses a limitation of
The parameter of interest
is A.
It
adjustment for the city and year fixed effects).
policy,
northern
households
can
between temperature and
Due
to the
respond
measured by
1.
Consequently, A provides a second
test
TSP
in
TSP
the south (after
Huai River/Qinling Mountains based
cold
to
temperatures
by
altering
Southern households do not have
consumption of heat derived from coal-based sources.
opportunity.
Model
in air
captures the marginal effect of winter temperature on
the north, as distinct from the relationship
heating
as well as
importantly, the city fixed effects removes permanent differences
unrestricted year effects,
in
6c,
their
this
for this policy's negative externalities,
air quality.
IV. Results
Figure 2 previews the Model
between a
latitude.
city's
The
average
fitted
TSP
values
TSP
1
results visually.
concentration calculated for
come from non-parametric
all
It
plots the bivariate relationship
available years from 1981-1993 and
regressions using Cleveland's (1979) tricube
weighting function and a bandwidth of
0.5, estimated separately for cities
Huai
Thus,
River/Qinling Mountains
concentration across latitude.
line.
The data
they
represent
a
points represent each city's
on either side of the
moving average of
mean TSP
the
concentration.
TSP
The
An
figure presents dramatic evidence that northern cities have higher
especially convincing feature of the graph
concentrations
at latitudes just
seems improbable
is
of
concentrations.
the evidence of a discontinuous increase in
above the Huai River
that other determinants
TSP
line.
jump
This
is
meaningful, because
change as discretely
air pollution
TSP
to the north
it
of the
heating policy.
line as the
We
begin by focusing on the Model
The column
the top panel of Table 2.
1
TSP
results,
which are
in the first
(1) specification controls for latitude.
columns of
three
Column
(2)
adds the
square of latitude as a covariate and column (3) adds a cubic term to the column (2) specification.
The
striking finding
from columns
roughly 300 mg/nv' higher
significant difference
is
in
(1)
and (2)
northern
more than
cities.
is
that annual
To
put this
average
in
in
TSP
to
be statistically different from zero
The Model
cities.
1
However, they
SO2 and NOx
at
statistically
that prevailed in the
1970.^ In the richer, but possibly over-
parameterized column (3) specification, the difference declines to about 200
be judged
concentrations are
perspective, this
three times the concentration of
United States before the passage of the Clean Air Act
TSP
mg/m
but
would
still
conventional levels.
results generally indicate higher concentrations in northern
are poorly determined and
none of them would be judged
to
be
statistically
significant at conventional levels.
We
also conducted a falsification exercise based on the location of the Yangtze River.
we
particular,
designated
others as southern cities.
hypothesis
fitting a
is
Since there
the north of this river as northern cities and classified the
is
not a heating policy based on the Yangtze River, the null
that pollution concentrations are equal to the north
version of
of higher
all cities to
TSP
Model
1
that utilizes theses
upon request, adjustment
and south of the
Yangtze-based designations
concentrations to the north of the Yangtze River.
In results available
In
for longitude
7
Similarly,
river.
fails to tlnd
we
Indeed,
evidence
cannot reject the
does not substantially affect the estimates of p.
null that
SO2 and NO^ concentrations
available
upon
are equal in the north and south of the
results.
The
point estimate indicates that across the entire sample there
The column
(1) specification
TSP
concentration
current U.S.
northern
in
TSP
months but the TSP concentration
a
1°
F decrease
in
the
Model
2
again
fails
calculated over 12 months.
is
mg/m^
(again
find
to
in
the annual
southern ones. This effect
winter temperature
concentrations of roughly 100
indicates that a 1° F decrease in
is
because the temperature variable
levels, especially
focus on the
between winter temperature and an
mg/m' increase
associated with a 24
cities, relative to
first
is
evidence of a relationship
is little
The estimate
indicator for the city being north of the heating line.
is
We
concentrations.
specification adds the interaction
(2)
2.
simply includes the main effect for winter temperature.
between winter temperature deviations and annual
the winter temperature
Model
presents the results from two versions of
TSP
The column
associated
also
is
mean
enormous
daily
concentrations
is
unexpected
inventories of emissions sources,
the
TSP
it
in
calculated during three
Indeed, the estimate implies that
with an
in the north, relative to
increase
in
winter
is
findings. Thus, at this point,
of the
TSP
TSP
the effect in the south).
evidence that the heating policy affects SO2 and
light
TSP
relative to
concentrations. This finding that the heating policy does not have a detectable impact on
NO^
(results
^
request).
The lower panel
Yangtze
results.
In
NOx
SO: and
the absence of city-level
unclear whether this finding casts doubt on the validity of
we simply
note the absence of an association between the
policy and concentrafions of these pollutants.
V. Discussion and Future Directions
Using
a
unique data
file
on
air pollution
concentration
in
76 Chinese
cities, this
paper has
demonstrated that the Huai River/Qinling Mountains heating policy leads
TSP
levels in northern China.
approach and
estimation
temperature on ambient
little
in
TSP
This result holds
a
panel
data
concentrations
in
a cross-sectional regression discontinuity-style
setting
in
compares the impact of changes
that
northern and southern
evidence that the heating policy leads to increases
More
to dramatically higher
in
SO2 and NOx
broadly, this paper has uncovered a source of variation
cities.
In contrast, there
concentrations
far
above those ever recorded
in
the
is
concentrations.
in air
pollution that can be
used to study the impacts of air quality on human health and individuals' valuations of clean
pollution
in
U.S.
or
air at
any other country.
Extrapolation from U.S. -based studies suggests that the costs of these levels of TSP are substantial
in
terms of
2003a,
b,
relatively
human
health and welfare
more generally (Kenneth Chay and Michael Greenstone,
and 2005; Kenneth Chay, Carlos Dobkin and Michael Greenstone, 2003). However, the
low
levels
unlikely to be valid.
of
An
air pollution
and high incomes
in the
important direction for future research
is
U.S.
mean
that extrapolation
to assess these costs in China.
is
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Table
1
:
Summary
Statistics for
Key
Variables
Obs.
Variable
Mean
Std.
Mill
Max
Dev.
(mg/m
399
449
538
401
Winter Temperature (°F)
455
Year
455
455
455
Total Suspended Particulates
)
Sulfur Dioxide (mg/m^)
Nitrogen Oxides (mg/m
Latitude
1
(°
)
North)
(North ot'Huai River)
Notes: The entries are calculated across
The data
all
330
80
2770
109
82.2
2
520
56.5
24.6
7
164
32.6
14.0
-1.6
66.6
1987
3.90
1981
1993
35.0
6.35
20.1
47.3
.613
.488
1
non-missing city observations during the 1980-1993
have a recorded concentration for at
Fifty-eight cities have at least one year of non-missing total
least one pollutant in one year.
suspended particulates data. The same 58 cities have at least one year of non-missing sulfur
period.
dioxide data.
A
tile is
total
unbalanced and a
of 41
cities
total
of 76
cities
have non-missing nitrogen oxides data.
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