Lived Effects of Historic Climate

¶ … Lived Effects of Historic Climate on the Wealth of Nations

bluedorn, john c., VALENTINYI, AKOS and VLASSOPOULOS, MICHAEL

The authors are attempting through their research to make a direct connection between the wealth and prosperity of nations when compared with the effects of long-term climate change, specifically temperature. They propose to conduct their study over three centuries time, the 18th, 19th, and 20th centuries (1730 to 2000) by observing the income data from cross sections of 167 countries. The use historical data sources and base their weighted scale on thirty-year average temperatures specifically oriented to countrywide variances. The major contribution of this particular study is to add to the current hypotheses that climatic temperature has a time-varying, non-monotonic effect upon income as observed in the 20th century and project bock to confirm this theory for the 18th and 19th centuries.

Their data infers that negative temperature changes in long-term weather patterns have a subsequent negative effect on the income distribution on a larger geographic scale. The outcome of this study is a country-level, population-weighted, scale of climatic temperatures over a 270 years time period. The authors admit that their results, while "robust to a host of sub-sample stability and specification checks,"

they are not altogether conclusive to a direct relationship. In fact the data from the 20th century does not parallel the implication of the data directly from the 18th and 19th century. Their conclusion is in fact that, "climatic temperature does not contribute a significant direct disadvantage for current economic outcomes."

The authors admit that while their findings from the data are indeed interesting that more work will need to be done, "A more detailed investigation of the postulated interpretations presented here are left for future research."

Correlation with the Relevant Literature

The authors cite numerous sources and appear, for the most part, to be correlative with the literature on the subject of the influence of temperature change and economic development. For instance in the article, "Climate Change and Economic Growth: Evidence from the Last Half Century"

the authors draw similar conclusions in that they correlate higher temperatures with downturn in economic development in poorer countries, while see little or no effect in richer countries. They also find that higher temperatures reduce growth rate in poorer countries as well and that higher temperatures have even wider ranging effects that just with the economy. These latter effects are only partially discussed in the Bludorn, et. al. article, but may have influences that affect their findings.

In the article, "Extreme Weather Events, Mortality, and Migration,"

the authors also discuss the impact that these event have on lower income countries who are not fortified sufficiently to overcome the hardships that present themselves. Furthermore, that Geography itself may have an increasing determent factor when it comes to economic development and survival in lower income countries. in, "Geography and Economic Development,"

the authors cite that, "When we identify geographical regions that are not conducive to modern economic growth, we find that many of these regions have high population density and rapid population increase."

These regions are not only affected by climactic change in different ways but may respond differently than some of the various samplings the authors of the Bludorn, et. al. article have taken into account.

Further Geographic and Geologic conditions also play a role in this asymmetrical affect. In the article, "Three Centuries of Global Population Growth: A Spatial Referenced Population (Density) Database for 1700-2000,"

which is one of the database reference for the Bludorn, et. al. research, the authors also note that climactic changes are consequential to geological and geographic changes and that the movement of the populations itself certainly contributes to the reapportionment of the landscape. This is particularly apparent during the industrial revolution when the "Old World' started to colonize the 'New World.'"

This effect also dates back to the Neolithic revolution as well especially when it comes the transition form agricultural to non-agricultural bases.

One of the Key components of the Bludorn, et. al. research is their incorporation of the data from the Northern Hemisphere mean annual temperature reconstruction of Mann, Bradley, and Hughes which is thoroughly analyzed in the article, "Robustness of the Mann, Bradley, Hughes Reconstruction of Northern Hemisphere Surface Temperatures: Examination of Criticisms Based on the Nature and Processing of Proxy Climate Evidence," their research uses PC's to more effectively correlate the data.

This data has proved robust, as the article indicates and thoroughly vetted by the authors and covers, "global/hemispheric surface temperatures that cover all or significant portions of the last millennium."

Critical Evaluation

While the authors of this article have certain done a well crafted research project, their evaluation of the findings become rather segmented for a global impact study. While they have studied the impact of temperatures on the economic growth of nations over a long period of time, their final conclusions are admittedly vague since the data for more current times contradicts the earlier constructions. They failed to take into complete consideration population growth and the impact that has on the landscape itself as well as the industrial effect of greenhouse gasses upon the population. One glaring omission is the concept of global warming as an important consideration that may affect the data in the more current century. While the authors used one source that particularly address this issue they only pulled the requisite data on colonial settler mortality and not global warming directly. In fact the concept of global warming economics is one that is also not addressed, however the brevity of their paper merely brings up more questions for future research, as the authors themselves indicate at the conclusion.

They did not fully explore, for example, the greenhouse effect which is a natural phenomenon that has been operating for millions of years and without it the Earth would be too cold to support life as we know it. Greenhouse gases such as carbon dioxide, methane, nitrous oxide and chloroflurocarbons (CFCs) in the atmosphere keep the Earth's mean surface temperature at an average of 59 degrees Fahrenheit. "Whilst the greenhouse effect is a naturally occurring phenomenon it is anthropogenic changes to the composition of greenhouse gases that has caused concern in the scientific community, the public and policy makers."

The follwing table may have helped further their research:

Figure 1: Greenhouse Gas Concentrations

This upward trend in greenhouse gases is, theoretically, the result of the waste material of modern civilization. From the pollution by factories to the increased methane produced by cows and other livestock man has cultivated in larger and larger numbers to sustain human beings. This process alone would be enough to skew the numbers that the authors data produced rendering the usual trend variances somewhat meaningless. Somewhat in that the report itself certainly has raised this very useful question of economic and climate change that should not be altogether ignored.