Identifier
Created
Classification
Origin
09CHENGDU95
2009-06-02 06:03:00
UNCLASSIFIED//FOR OFFICIAL USE ONLY
Consulate Chengdu
Cable title:  

SOUTHWEST CHINA: WHAT'S GOING ON WITH AIR QUALITY DATA?

Tags:  SENV CH ENRG PREL ECON 
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ZNR UUUUU ZZH
R 020603Z JUN 09
FM AMCONSUL CHENGDU
TO RUEHC/SECSTATE WASHDC 3243
INFO RUEHOO/CHINA POSTS COLLECTIVE
RUEAEPA/EPA WASHINGTON DC
RUCPDOC/DEPT OF COMMERCE WASHINGTON DC
RUEATRS/DEPT OF TREASURY WASHINGTON DC
RHMFISS/DEPT OF ENERGY WASHINGTON DC
RUEHCN/AMCONSUL CHENGDU 3916
UNCLAS SECTION 01 OF 02 CHENGDU 000095 

SENSITIVE
SIPDIS

DEPT FOR EAP/CM

E.O. 12958: N/A
TAGS: SENV CH ENRG PREL ECON
SUBJECT: SOUTHWEST CHINA: WHAT'S GOING ON WITH AIR QUALITY DATA?

REF: 2008 CHENGDU 210

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UNCLAS SECTION 01 OF 02 CHENGDU 000095

SENSITIVE
SIPDIS

DEPT FOR EAP/CM

E.O. 12958: N/A
TAGS: SENV CH ENRG PREL ECON
SUBJECT: SOUTHWEST CHINA: WHAT'S GOING ON WITH AIR QUALITY DATA?

REF: 2008 CHENGDU 210

CHENGDU 00000095 001.2 OF 002



1. (SBU) This cable contains sensitive but unclassified
information - not for distribution on the Internet.




2. (SBU) SUMMARY: Air quality in Southwest China's city of
Chengdu, is probably worse than official statistics would
suggest. The city records significantly fewer poor air quality
days than should normally occur based on a statistical analysis
of the government's air quality data. Even air quality that has
a strong odor and limits visibility is sometimes recorded as
being only "lightly polluted." City residents in May reportedly
called local media outlets to question the disparity between
official air quality figures and air they saw outside.
Defensive of their data, city environmental officials claim
pollution is often localized and lasts for only short periods
throughout the day. END SUMMARY.




3. (SBU) Air quality in Sichuan's capital city of Chengdu is on
track to record more relatively low pollution days in 2009 than
at any time since 2001, based on government data available for
the first five months. Through May, Chengdu had 124 days with
"very good" air quality, defined as days on which the air
pollution index (API) is 100 or lower. Air quality monitors
currently measure only sulfur dioxide, nitrogen dioxide, and
large particulates, neglecting other pollutants like ozone and
fine particulates. Chengdu may record 329 days of very good air
by the end of the year, roughly 90 percent of time, if the
pattern seen in our analysis of the data from previous years
continues. Past data from the city's Environmental Protection
Bureau shows that air quality generally improves after the
winter months. Over the last five years, Chengdu's air quality
statistics show that the number of very good quality air days
increased 7 percent on average from June 1 through the end of
the year.



When "Choking" Air Equals Light Pollution

--------------




4. (SBU) Despite the apparent success and the potential for
full-year improvements in air quality, the city's data appears
to show the same potential for manipulation Post has seen in
reviewing the last nine years of reported measurements. Days on

which air quality probably did not reach the very good threshold
were nevertheless recorded as "very good." We see an excessive
number of days during the first five months of this year where
pollution data falls outside the normal distribution one would
expect to see. Through the end of May 2009, Chengdu recorded
about 60 more days with an API of 46-100, and roughly 25 fewer
days of API 100-150 than would occur if the data had a normal
distribution. Note: Normal distribution, also called Gaussian
distribution, has long been used as a basis for analyzing air
quality. In a normal distribution, a large number of
independent data points will tend to follow a bell curve
specific to the data set being analyzed. Chengdu's air quality
data has significant variations from this curve, particularly
around the cutoff point between lightly polluted and very good
air quality.




5. (SBU) The annual burning of agricultural stalks around
Chengdu during May in fact resulted in noticeably poor air
quality for the city's residents. The resulting pollution
decreased visibility in the downtown area and gave the air a
distinctive smell. A local Chinese-language news service,
Sichuan Online, reported that on 18 May some city residents were
calling the newspaper to ask about the difference between the
published figures and the perceived air quality. The newspaper
wrote that "pervasive smoke" on May 17 and 18 "choked people,"
but official figures show that the API for both days was 65,
very good, and 104, lightly polluted, respectively. A Sichuan
Evening News reporter said that on 17 May visibility in
Chengdu's northwestern district of Jinniu was less than 100
meters, and drivers were forced to significantly reduce their
speed while driving. A picture included with the news article
showed a thick shroud of pollution in what appears to be
downtown Chengdu. Congenoff also noted the smell of burning

CHENGDU 00000095 002.2 OF 002


agricultural stalks south of the city center. The Chengdu city
government officially prohibits the burning of agricultural
stalks, and may assess a fine of USD 29 or less for farmers
found violating the regulation. Burning is common in spite of
the ban.



Why the Inconsistency?

--------------




6. (SBU) Chengdu environmental officials tell us that air
quality is measured daily from noon to noon, meaning that each
recorded day of data actually includes the afternoon and evening
hours from the previous day. Monitors placed at 38 sites around
the city log pollution data and transmit it to the Chengdu
Environmental Supervision Center (CESC). The results for the
24-hour period are then transmitted to Beijing and select
officials across Chengdu. Some of these officials receive text
messages each afternoon on their cell phones with the day's air
quality before it is publicly available.




7. (SBU) CESC officials claimed recently that the discrepancy
between some residents' perceptions of pollution and the
recorded air quality resulted from brief periods of peak
pollution that were not sustained over a 24-hour reporting
period. They also explained that different parts of the city
experience differing levels of pollution. On a day when air
quality around several parts of the city appeared very poor,
however, no monitoring station recorded higher than lightly
polluted air. CESC said that monitoring stations around Chengdu
registered API values ranging from 102-130 between noon on 17
May and noon the following day. The official average for the
day was only 104, suggesting that the majority of stations
around the city recorded at, or very close to, the bottom of the
range. Reviewing the CESC data, we estimate that no more than
one or two monitoring station reached 130, and few stations
could have recorded a value higher than 110.




8. (SBU) Comment: We are unclear if the air quality monitors
around the city record better than expected air quality because
of the locations of the monitors or because CESC officials
actually manipulate the data once they receive it. The one air
monitoring station that Congenoff was able to visit in February
did not seem like its location would provide artificially good
air quality readings. Officials showed Congenoff the modem in
the monitoring station that enabled the data transfer to CESC,
but Congenoff has not had an opportunity to see where the data
from all of the monitoring stations is aggregated. We do not
know if any of the air quality monitoring stations have been
moved over the last several years.
BOUGHNER