New Evidence That the Ancient Climate Was Warmer than Today’s

Two recently published studies confirm that the climate thousands of years ago was as warm or warmer than today’s – a fact disputed by some believers in the narrative of largely human-caused global warming. That was an era when CO₂ levels were much lower than now, long before industrialization and SUVs.

One study demonstrates that the period known as the Roman Warming was the warmest in the last 2,000 years. The other study provides evidence that it was just as warm up to 6,000 years ago. Both studies reinforce the occurrence of an even warmer period immediately following the end of the last ice age 11,000 years ago, known as the Holocene Thermal Maximum.

The first study, undertaken by a group of Italian and Spanish researchers, reconstructed sea surface temperatures in the Mediterranean Sea over the past 5,300 years. Because temperature measurement using scientific thermometers goes back only to the 18th century, temperatures for earlier periods must be reconstructed from proxy data using indirect sources such as tree rings, ice cores, leaf fossils or boreholes.

This particular study utilized fossilized amoeba skeletons found in seabed sediments. The ratio of magnesium to calcium in the skeletons is a measure of the seawater temperature at the time the sediment was deposited; a timeline can be established by radiocarbon dating. The researchers focused on the central part of the Mediterranean Sea, specifically the Sicily Channel as indicated by the red arrow in the figure below. The samples came from a depth of 475 meters (1,550 feet).

Analysis of the data found that ancient sea surface temperatures in the Sicily Channel ranged from 16.4 degrees Celsius (61.5 degrees Fahrenheit) to 22.7 degrees Celsius (72.9 degrees Fahrenheit) over the period from 3300 BCE to July 2014. This is illustrated in the next figure, in which the dark blue dashed line represents the Sicily Channel raw temperature data and the thick dark blue solid line shows smoothed values. The other lines are Mediterranean temperatures reconstructed by other research groups.

With the exception of the Aegean data, the results all show distinct warming during the Roman period from 0 CE to 500 CE, when temperatures were about 2 degrees Celsius (3.6 degrees Fahrenheit) higher than the average for Sicily and western Mediterranean regions in later centuries, and much higher than present-day Sicilian temperatures. The high temperatures in the Aegean Sea result from its land-locked nature. During the 500 years of the Roman Warming, the Roman Empire flourished and reached its zenith. Subsequent cooling, seen in the figure above, led to the Empire’s collapse prior to the Medieval Warm Period, say the researchers.

The second study was conducted by archaeologists in Norway, who discovered a treasure trove of arrows, arrowheads, clothing and other artifacts, unearthed by receding ice in a mountainous region of the country. Because the artifacts would have been deposited when no ice covered the ground, and are only being exposed now due to global warming, temperatures must have been at least as high as today during the many periods when the artifacts were cast aside.

The oldest arrows and artifacts date from around 4100 BCE, the youngest from approximately 1300 CE, at the end of the Medieval Warm Period. That the artifacts come from several different periods separated by hundreds or thousands of years implies that the ice and snow in the region must have expanded and receded several times over the past 6,000 years.

During the Holocene Thermal Maximum, which occurred from approximately 10,000 to 6,000 years ago and preceded the period of the stunning Norwegian discoveries, global temperatures were higher yet. In upper latitudes, where the most reliable proxies are found, it was an estimated 2-3 degrees Celsius (3.6-5.4 degrees Fahrenheit) warmer than at present. The warmth contributed to the rise of agricultural societies around the globe and the development of human civilization.

Paradoxically though, the Greenland ice sheet – the present melting of which has sparked heated debate – is thought to have been even larger at the peak of the Holocene Thermal Maximum than it is today, when Greenland temperatures are lower. This can be seen in the following figure, showing that the ice sheet extent was about the same as now about 7,500 years (7.5 ka) ago, and even greater before that. The ice did, however, retract to a minimum during the intervening period (up to 7.5 ka ago) that includes both the Roman Warming and the period of the Norwegian discoveries discussed above.

Puzzles like this mean that we still have much to learn about the earth’s climate, both past and present, especially in the area of natural variability.

Next: What Triggered the Ice Ages?  The Uncertain Role of CO2

No Evidence That 2020 Hurricane Season Was Record-Breaking

In a world that routinely hypes extreme weather events, it’s no surprise that the mainstream media and alarmist climate scientists have declared this year’s Atlantic hurricane season “unprecedented” and “record-shattering.” But the reality is that the season was merely so-so and no records fell.

While it’s true that the very active 2020 season saw a record-breaking 30 named storms, only 13 of these became hurricanes. That was fewer than the historical high of 15 recorded in 2005 and only one more than the 12 hurricanes recorded in 1969 and 2010, according to NOAA (the U.S. National Oceanic and Atmospheric Administration). The figure below shows the frequency of all Atlantic hurricanes from 1851 to 2020.

Of 2020’s 13 hurricanes, only six were major hurricanes, less than the record eight in 1950 and seven in 1961 and 2005, as shown in the next figure. A major hurricane is defined as one in Category 3, 4 or 5 on the so-called Saffir-Simpson scale, corresponding to a top wind speed of 178 km per hour (111 mph) or greater. Although it appears that major Atlantic hurricanes were less frequent before about 1940, the lower numbers reflect the relative lack of observations in early years of the record. Aircraft reconnaissance flights to gather data on hurricanes only began in 1944, while satellite coverage dates only from the 1960s.

Despite the lack of any significant trend in Atlantic hurricanes in a warming world, the frequency of hurricanes globally is actually diminishing as seen in the following figure. The apparent slight increase in major hurricanes since 1981 has been ascribed to improvements in observational capabilities, rather than warming oceans that provide the fuel for hurricanes and typhoons.

As further evidence that recent hurricane activity is nothing unusual, the figure below depicts what is known as the ACE (Accumulated Cyclone Energy) index for the Atlantic basin from 1855 to 2020. The ACE index is an integrated metric combining the number of storms each year, how long they survive and how intense they become. Mathematically, the index is calculated by squaring the maximum sustained wind speed in a named storm every six hours that it remains above tropical storm intensity and summing that up for all storms in the season.

For 2020, the Atlantic basin ACE index was 179.8, which ranks 13th behind 2017, 2005, the peak in 1933 and nine other years. For comparison, this year’s ACE index for the northwestern Pacific, where typhoons are common, was 148.5. The higher value for the Atlantic this year reflects the greater number of named storms.

NOAA attributes the enhanced number of atmospheric whirligigs in the Atlantic in recent years to the warm phase of the naturally occurring AMO (Atlantic Multi-Decadal Oscillation). The AMO, which has a cycle time of approximately 65 years and alternates between warm and cool phases, governs many extremes, such as cyclonic storms in the Atlantic basin and major floods in eastern North America and western Europe. The present warm phase began in 1995, marking the beginning of a period when both named Atlantic storms and hurricanes have become more common on average – as seen in the first two figures above.

Another contribution to storm activity in the Atlantic comes from La Niña cycles in the Pacific. Apart from a cooling effect, La Niñas result in quieter conditions in the eastern Pacific and heightened activity in the Atlantic. The current La Niña started several months ago and is expected to continue into 2021.

Despite NOAA’s recognition of what has caused so many Atlantic storms in 2020, activists continue to claim that climate change is making hurricanes stronger and more destructive and increasing the likelihood of more frequent major hurricanes. Pontificates Michael “hockey stick” Mann: “The impacts of climate change are no longer subtle. We’re seeing them play out right now in the form of unprecedented wildfires out West and an unprecedented hurricane season back East.”

Clearly, there’s no evidence for such nonsensical, unscientific statements.

Next: New Evidence That the Ancient Climate Was Warmer than Today’s