Learn how plants respond to higher atmospheric CO2 concentrations

How does rising atmospheric CO2 affect marine organisms?

Click to locate material archived on our website by topic


The 1958-2000 Temperature History of the Tibetan Plateau
Volume 8, Number 9: 2 March 2005

The World ran Mad, and each distempered Brain,
Did Strange and different Frenzies entertain.

Some 23 years ago, Idso (1982) borrowed this 300-year-old couplet from Mrs. Aphra Behn to introduce the second chapter of his first self-published book, wherein he took issue with what he called the "establishment viewpoint" of an impending CO2-induced catastrophic climate change.  Today, the verse seems even more appropriate, as political figures at the highest levels of many national governments are attempting to convince the populace of the planet that our burning of fossil fuels has brought us to the brink of a global climatic meltdown, as they insist that over the past quarter-century the world has warmed at an unprecedented rate that has driven the temperature of the globe to a level not experienced in the prior two millennia.

In combating this false dogma, we regularly draw attention to the fact that numerous scientific studies from all around the world have demonstrated that it was equally as warm as it is now, or maybe even warmer, during parts of both the Medieval and Roman Warm Periods, when there was fully 100 ppm less CO2 in the air than there is currently; and we likewise report the findings of studies that show little to no warming over large parts of the earth over the last four to seven decades (see Temperature (Trends) in our Subject Index), including many studies that actually reveal cooling over this period (for several examples, see Temperature (Trends - Antarctic and Arctic).

Continuing in this mode of operation, we here report the findings of a most interesting study of the thermal history of the Tibetan Plateau (TP), the highest and largest plateau on earth, which was conducted by Frauenfeld et al. (2005), who approached the task from two different perspectives.  In the first approach they used daily surface air temperature measurements from 161 stations located throughout the TP to calculate the region's mean annual temperature for each year from 1958 through 2000, while in the second approach they used 2-meter temperatures from the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis (ERA-40), which temperatures, in their words, "are derived from rawinsonde profiles, satellite retrievals, aircraft reports, and other sources including some surface observations."  This latter approach, according to them, results in "more temporally homogeneous fields" that provide "a better assessment of large-scale temperature variability across the plateau."

So what did they find?

Frauenfeld et al. report that over the period 1958-2000, "time series based on aggregating all station data on the TP show a statistically significant positive trend of 0.16C per decade," as has also been reported by Liu and Chen (2000).  However, they report that "no trends are evident in the ERA-40 data for the plateau as a whole."

In discussing this discrepancy, the three scientists suggest that "a potential explanation for the difference between reanalysis and station trends is the extensive local and regional land use change that has occurred across the TP over the last 50 years."  They note, for example, that "over the last 30 years, livestock numbers across the TP have increased more than 200% due to inappropriate land management practices and are now at levels that far exceed the carrying capacity of the region (Du et al., 2004)."  The resultant overgrazing, in their words, "has caused land degradation and desertification at an alarming rate (Zhu and Li, 2000; Zeng et al., 2003)," and they note that "in other parts of the world, land degradation due to overgrazing has been shown to cause significant local temperature increases (e.g., Balling et al., 1998)."

Another point they raise is that "urbanization, which can result in 8-11C higher temperatures than in surrounding rural areas (e.g., Brandsma et al., 2003), has also occurred extensively on the TP," noting that "construction of a gas pipeline in the 1970s and highway expansion projects in the early 1980s have resulted in a dramatic population influx from other parts of China, contributing to both urbanization and a changed landscape."  In this regard, they say that "the original Tibetan section of Lhasa (i.e., the pre-1950 Lhasa) now only comprises 4% of the city, suggesting a 2400% increase in size over the last 50 years."  And they add that "similar population increases have occurred at other locations across the TP," and that "even villages and small towns can exhibit a strong urban heat island effect."

In concluding their analysis of the situation, Frauenfeld et al. "submit that these local changes are reflected in station temperature records."  We agree; and we note that when these surface-generated anomalies are removed, as in the case of the ERA-40 reanalysis results they present, it is clear that there has been no warming of the Tibetan Plateau since at least 1958.

Sherwood, Keith and Craig Idso

References
Balling Jr., R.C., Klopatek, J.M., Hildebrandt, M.L., Moritz, C.K. and Watts, C.J.  1998.  Impacts of land degradation on historical temperature records from the Sonoran desert.  Climatic Change 40: 669-681.

Behn, A.  1688.  A Poem to Sir Roger L'Estrange on his third Part of the History of the Times, Relating to the Death of Sir Edmund Bury-Godfrey.

Brandsma, T., Konnen, G.P. and Wessels, H.R.A.  2003.  Empirical estimation of the effect of urban heat advection on the temperature series of DeBilt (the Netherlands).  International Journal of Climatology 23: 829-845.

Du, M., Kawashima, S., Yonemura, S., Zhang, X. and Chen, S.  2004.  Mutual influence between human activities and climate change in the Tibetan Plateau during recent years.  Global and Planetary Change 41: 241-249.

Frauenfeld, O.W., Zhang, T. and Serreze, M.C.  2005.  Climate change and variability using European Centre for Medium-Range Weather Forecasts reanalysis (ERA-40) temperatures on the Tibetan Plateau.  Journal of Geophysical Research 110: 10.1029/2004JD005230.

Idso, S.B.  1982.  Carbon Dioxide: Friend or Foe? An Inquiry into the Climatic and Agricultural Consequences of the Rapidly Rising CO2 Content of Earth's Atmosphere.  IBR Press, Tempe, AZ.

Liu, X. and Chen, B.  2000.  Climatic warming in the Tibetan Plateau during recent decades.  International Journal of Climatology 20: 1729-1742.

Zeng, Y., Feng, Z. and Cao, G.  2003.  Land cover change and its environmental impact in the upper reaches of the Yellow River, northeast Qinghai-Tibetan Plateau.  Mountain Research and Development 23: 353-361.

Zhu, L. and Li, B.  2000.  Natural hazards and environmental issues.  In: Zheng, D., Zhang, Q. and Wu, S. (Eds.)  Mountain Genecology and Sustainable Development of the Tibetan Plateau, Springer, New York, New York, USA, pp. 203-222.