Beware of Misleading Records

What is wrong with the following headline?

Answer: It doesn’t state which record the UN is referring to.

So, which record is it?

Answer: the instrumental temperature record, a.k.a. the record made with the use of thermometers.

From Nature Communications: “The geological record and simulations of past climate provide scientists with the opportunity to understand how Earth system processes operate outside the observational or instrumental record, and are fundamental to our understanding and ability to accurately project future climate and environmental change.”

How far back does the instrumental temperature record go?

Answer: no further than the year 1714 CE.

Prior to Year 1714 CE, people did not have a way to make accurate temperature measurements.

So, when the UN says that the current decade will be the hottest decade on record, what the UN means is that the current decade will be the hottest decade of the last 300 years.

Plenty of eras in Earth’s history were as hot as the present era if not hotter. An example of such is the mid-Pliocene Warm Period, which took place from 3.6 million years ago to 2.58 million years ago.

Again from Nature Communications:

Both palaeoenvironmental reconstructions and climate modelling have been pivotal in increasing our understanding of climate and its importance during the mid-Pliocene Warm Period (mPWP: 3.264–3.025 Ma; also referred to as the ‘Pliocene Research, Interpretation and Synoptic Mapping (PRISM) interval’). During warm intervals of the Pliocene, atmospheric CO2 concentration is estimated to have ranged between 350 and 450 p.p.m.v. This is in contrast to the known pre-industrial concentration of 280 p.p.m.v. On the basis of palaeoenvironmental reconstruction, Pliocene surface temperatures over land and oceans were elevated with respect to the pre-industrial. Climate model estimates indicate that the global annual mean surface temperature was 2.7–4.0°C higher. A combination of modelling studies and geological data has shown, for example, that during the mPWP the hydrological cycle was enhanced, ice sheets were smaller, sea level was higher, forest cover was expanded and arid deserts contracted.

Granted, the Earth’s climate will still be getting warmer because of what the Sun is doing.

For what it’s worth, here are graphs showing the geological record of past climate.

The above graphs are from the IPCC’s 1990 report.

Featured Image by EverythingSuperMario.

Licensed under the Creative Commons Attribution-Share Alike 4.0 International license.

The post Beware of Misleading Records appeared first on The Moderate Voice.