New study shows half of the global warming in the USA is artificial
Posted on July 29, 2012 by Anthony Watts
PRESS RELEASE – U.S. Temperature trends show a spurious doubling due to NOAA station
siting problems and post measurement adjustments.
Chico, CA July 29th, 2012 – 12 PM PDT – FOR IMMEDIATE RELEASE
A comparison and summary of trends is shown from the paper. Acceptably placed thermometers
away from common urban influences read much cooler nationwide:
A reanalysis of U.S. surface station temperatures has been performed using the recently
WMO-approved Siting Classification System devised by METEO-France’s Michel Leroy.
The new siting classification more accurately characterizes the quality of the location
in terms of monitoring long-term spatially representative surface temperature trends.
The new analysis demonstrates that reported 1979-2008 U.S. temperature trends are
spuriously doubled, with 92% of that over-estimation resulting from erroneous NOAA
adjustments of well-sited stations upward. The paper is the first to use the updated
siting system which addresses USHCN siting issues and data adjustments.
The new improved assessment, for the years 1979 to 2008, yields a trend of +0.155C
per decade from the high quality sites, a +0.248 C per decade trend for poorly sited
locations, and a trend of +0.309 C per decade after NOAA adjusts the data. This issue
of station siting quality is expected to be an issue with respect to the monitoring
of land surface temperature throughout the Global Historical Climate Network and
in the BEST network.
Today, a new paper has been released that is the culmination of knowledge gleaned
from five years of work by Anthony Watts and the many volunteers and contributors
to the SurfaceStations project started in 2007.
This pre-publication draft paper, titled An area and distance weighted analysis of
the impacts of station exposure on the U.S. Historical Climatology Network temperatures
and temperature trends, is co-authored by Anthony Watts of California, Evan Jones
of New York, Stephen McIntyre of Toronto, Canada, and Dr. John R. Christy from the
Department of Atmospheric Science, University of Alabama, Huntsville, is to be submitted
The Chinese demonstrate that UHI has a real and essential effect on regional climate
Posted on May 13, 2013 by Anthony Watts
Study finds that urbanization has considerable influence on the regional climate
change, they even blame proximity to air-conditioning as a factor.
Press release from Science China Press (full paper follows)
Urbanization and surface warming in eastern China
A recent study indicated that the urbanization in eastern China has significant impact
on the observed surface warming and the temporal-spatial variations of urbanization
effect have been comprehensively detected.
This work was led by YANG XiuQun, professor of meteorology in the Institute for Climate
and Global Change Research, School of Atmospheric Sciences at Nanjing University.
The article entitled “Urbanization and heterogeneous surface warming in eastern China”
was published in Chinese Science Bulletin, 2013, No. 12.
Urbanization, as one of the most significant processes in land use/cover change,
can not only alter surface vegetation distribution, but also affect surface energy
and water balance. Some previous studies indicated that urbanization has little impact
on surface warming. However, recent investigations have suggested that urbanization
plays an essential role in regional climate change.
China has been experiencing intensive urbanization since the 1980s. Due to close
ties in social and economic aspects, single cities have expanded to form distinctive
city clusters in eastern China, such as the Beijing-Tianjin-Hebei (BTH), Yangtze
River Delta (YRD) and Pearl River Delta (PRD) city clusters. Combining the social
needs with scientific issues, Professor YANG XiuQun and his group dedicate to explore
the climatic effect of urbanization in eastern China from observation and simulation
perspectives. The objective of their work is to estimate the effect of urbanization
on surface air temperature (SAT) change, detect the seasonal variation of urban warming
in different regions, and analyze the impact of urbanization on maximum and minimum
With the homogeneity-adjusted SAT data at 312 stations in eastern China for 1979-2008
and the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS)
nighttime light data, the spatial heterogeneities of the SAT trends on different
scales are detected and the impact of urbanization in eastern China on surface warming
Results show that the urbanization can induce a remarkable summer warming in YRD
city cluster region and a winter warming in BTH city cluster region. The YRD warming
in summer primarily results from the significant increasing of maximum temperature,
with an estimated urban warming rate at 0.132-0.250°C per decade, accounting for
36%-68% of the total regional warming. The BTH warming in winter is primarily due
to the remarkable increasing of minimum temperature, with an estimated urban warming
rate at 0.102-0.214°C per decade, accounting for 12%-24% of the total regional warming.
The study finds that urbanization has considerable influence on the regional climate
change. Therefore, a more reasonable urban planning should be considered in order
to mitigate regional surface warming. In addition, the climatic effect of urbanization
features obvious temporal-spatial differences, which may be associated with the variation
of regional climatic background and the change of anthropogenic heat release. Detection
and assessment of the climatic effect of urbanization is of great significance for
further understanding the relationship between urban development and climate change.
This work was supported by the National Basic Research Program of China (2010CB428504).
Wu K, Yang X Q. Urbanization and heterogeneous surface warming in eastern China.
Chin Sci Bull, 58(12):1363-1373, doi: 10.1007/s11434-012-5627-8
Science China Press Co., Ltd. (SCP) is a scientific journal publishing company of
the Chinese Academy of Sciences (CAS). For 50 years, SCP takes its mission to present
to the world the best achievements by Chinese scientists on various fields of natural