By Daniel W Nebert

This summer there have been “scorching heat waves,” from the Pacific Northwest and New England to Northern Europe and Japan. We heard about a record-breaking 90°F in Sodankyla, Finland (north of the Arctic Circle) — hailed as “the latest evidence of global warming.” Europe and Greece reported severe hot days this summer. However, “one swallow does not a summer make.” Nor does “one hot summer ‘global warming’ make.”

Is 2018 the hottest year on record? Is 2017 the second-hottest year on record? The answer is: “No. Not even close.”

For example, several record-breaking highs in North America include: 100°F at Fort Yukon, Alaska (1915); 113°F in Saskatchewan (1937); 112°F in British Columbia (twice in 1941); 112°F in Manitoba (1936); 110°F in Alberta (1931); 108°F in Ontario (1919 & 1936); and 119°F in the State of Oregon (1898). The warming period in North America and Europe in the 1930s-40s was hotter than that in the 1980s-90s. Global temperatures have slightly declined since the 1997 peak.

But — these are times when we had thermometers to measure temperature. The German physicist Daniel Fahrenheit invented the mercury thermometer in 1714.

Before thermometers, we know the planet experienced: [a] The Minoan Warm Period (~1500 B.C. to 1000 B.C., supported by Greenland ice-core data); [b] The Roman Warm Period (~250 B.C. to 400 A.D., in Europe and the North Atlantic); and [c] The Medieval Warm Period (~950 to 1250 A.D., in the North Atlantic region, but also in China).

During the Medieval Warm Period, Vikings colonized southwestern Greenland; grape-growing and wine-making were well known — not only in England — but even near Stockholm. This warm period was followed by the Little Ice Age (~1550 to 1850), including a period of low solar activity, known as the Maunder Minimum (1645-1715); during this time the Thames River sometimes froze over.

In conclusion, temperatures recorded by thermometers represent “weather,” while the three above-described warm periods reflect “climate.” Therein lies the difference. “Weather” is recorded in days, months and years. “Climate” — measured as three 30-year periods per century — embodies centuries.

“Climate change” has been occurring since Earth first formed 4.54 billion years ago. Greenland and Antarctica ice–core records spanning the last 800,000 years indicate “Glacial-Interglacial Cycles” occur every ~110,000 years. Also known are: “Precession Cycles (every ~26,000 years), “Lunar Tidal Cycles” (~1800 years), “Sunspot Cycles” (on average, every eleven years), El Niño and its opposite La Niña (every two to seven years), and at least eight other cycles. These phases overlap with one another, i.e. global atmospheric temperatures rise, then fall, then rise again — affected by more than twelve climate cycles due to “natural causes.”

These natural causes include both terrestrial and extraterrestrial events. Because we live on a fluid planet having expansive oceans and atmosphere that are never in equilibrium, natural changes in climate are to be expected. Large differences in land:sea ratio between the Northern and Southern Hemisphere keep our weather exciting. Also, solar activity — which manifests itself as sunspots, with intense magnetic fields that become frozen into the solar wind and carried far beyond the solar system — sweeps galactic cosmic rays out of the the inner solar system; this has a profound influence on cloud formation and, therefore, Earth’s albedo (proportion of incident light, or radiation, reflected by a surface).

Additional changes in “total solar irradiance” cause the amount of energy (deposited in the various atmospheric layers) to fluctuate. Furthermore, oscillations in Earth’s orbit (Milankovitch Cycles) produce the dramatic Ice Ages and brief Interglacial periods. Finally, changes in volcanic activity and radiative forcing can also influence climate. The bottom line is that most of the climate drama occurs in our oceans — because they contain, by far, the most mobile heat on Earth and are constantly changing the heat distribution.

Thermometer measurements on very limited portions of Earth’s surface have always been subject to large variability due to local effects, which is why we have had satellite-measured global atmospheric temperatures recorded every minute since December 1978. From 1982 until 2014, my late son, employed by the U.S. Geological Survey, spearheaded meta-analysis of these satellite data — searching for evidence of a “statistically significant contribution of human activity” to global warming; he found none. Of course, we will continue to look.

CO 2 is a natural constituent of Earth’s atmosphere — not a “pollutant.” Without atmospheric CO 2 , there would be no agriculture and actually no carbon-based life on Earth. Global atmospheric CO 2 levels have increased steadily from ~280 parts-per-million in 1750 to ~414 today, but were as high as ~7,000 ppm during the Cambrian Period (~541-485 million years ago) when plant life flourished, i.e. any impact of CO 2 on climate is negligible.

Everything stated above is scientific fact. However, the United Nations’ Intergovernmental Panel on Climate Change (IPCC), National Oceanic and Atmospheric Administration (NOAA), and other governmental agencies have inexplicably chosen to “adjust their data” (i.e. “cook the books”) over the past 2-3 decades. This malfeasance has been propagated in the internet, many scientific professional societies, and journals such as Science , Nature , Scientific American , National Geographic , Time and Newsweek .

The last time we did a Google search for “global warming,” among the top 24 “hits” were sixteen having subjective, political or false information — instead of scientific data; the reasoning behind such propaganda being spewed forth is perplexing. Our only explanation is that the “Global Warming/Green Energy” Movement by environmentalists has snowballed into a trillion-dollar industry. And this includes many disreputable “scientists” whose salaries and grant money depend on their perpetuating this global warming myth.

Daniel W Nebert is professor emeritus from the University of Cincinnati.