Climate and Human Civilization for the Past 4,000 Years

By Andy May – Re-Blogged From http://www.WattsUpWithThat.com

The Holocene Thermal Optimum ended at different times in different parts of the world, but it had ended everywhere by 4,000 BP (BP here means the number of years before 2000) and the world began to cool. The timeline shown in Figure 1 shows the GISP2 Central Greenland ice core temperature proxies in blue and the HadCRUT 4.4 surface temperature estimates for the same area in red.

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Figure 1 (click on the figure to download in full resolution)

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Long -Term Climate Change: What Is A Reasonable Sample Size?

By Dr. Tim Ball – Re-Blogged From http://www.WattsUpWithThat.com

Recent discussion about record weather events, such as the warmest year on record, is a totally misleading and scientifically useless exercise. This is especially true when restricted to the instrumental record that covers about 25% of the globe for at most 120 years. The age of the Earth is approximately 4.54 billion years, so the sample size is 0.000002643172%. Discussing the significance of anything in a 120-year record plays directly into the hands of those trying to say that the last 120-years climate is abnormal and all due to human activity. It is done purely for political propaganda, to narrow people’s attention and to generate fear.

The misdirection is based on the false assumption that only a few variables and mechanisms are important in climate change, and they remain constant over the 4.54 billion years. It began with the assumption of the solar constant from the Sun that astronomers define as a medium-sized variable star. The AGW proponents successfully got the world focused on CO2, which is just 0.04% of the total atmospheric gases and varies considerably spatially and temporally. I used to argue that it is like determining the character, structure, and behavior of a human by measuring one wart on the left arm. In fact, they are only looking at one cell of that wart for their determination.

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Climate and Human Civilization Over the Last 18,000 Years

By Andy May – Re-Blogged From http://www.WattsUpWithThat.com

This is an updated timeline of climatic events and human history for the last 18,000 years. The original timeline was posted in 2013. The updated full size (Ansi E size or 34×44 inches) Adobe Reader version 8 PDF can be downloaded here or by clicking on Figure 1. It prints pretty well on 11×17 inch paper and very well on 17×22 inch paper or larger. To see the timeline in full resolution or to print it, you must download it. It is not copyrighted, but please acknowledge the author if you use it.

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Figure 1 -click for a much larger, printable poster (PDF)

References to the images and data are given in this essay as hyperlinks. I’ve done my best to verify the accuracy of the content by checking multiple sources. When references had different dates for the same event, I chose the most commonly cited date or the most prestigious source. All dates (except some in the modern era) are given as “BP” or before the year 2000 for simplicity, using 1950 (the radiocarbon zero) was too cumbersome.

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First Peoples: The Warming Alarm-Dog That Didn’t Bark

By Alec Rawls – Re-Blogged From http://www.WattsUpWithThat.com

Beneficial climate change allowed modern humans to emigrate out of Africa and spread around the globe says the new PBS documentary “First Peoples,” but it fails to mention that the era it designates as “good times” was several degrees warmer than today.

A critical moment in human history is intoned with intense drama (21:08-21:52 here):

The movement of prehistoric people was affected by the climate, which fluctuated over thousands of years.

I turned up the volume, knowing that if there was anything a warming alarm-dog could find to bark about, it was about to be featured front and center.

In bad times the Sahara was an un-crossable barrier, but in good times, when the climate was wet, the desert disappeared. Any adaption that emerged in one part of Africa could spread to other parts of the continent….

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