It has by now become common practice for just about any and every unusual weather occurrence, extreme temperature anomaly, or seismic event to be somehow, someway linked to the human practice of using energy derived from fossil fuels. No hurricane, flood, drought, storm, wildfire … is spared from potential anthropogenic implication.
Last week, a named hurricane (Hermine) that ultimately devolved into a tropical storm landed along the Florida coast — the first landfall in 11 years. As expected, the usual suspects reflexively blamed the storm on humans.
When a volcano erupts, the headliners are quick to point out that humans have made volcanic eruptions more likely.
When wildfires consume the landscape, human-caused warming is claimed to be fueling them.
In one year, human-caused warming can be said to be a cause of catastrophic drought in Texas.
A few years later, human-caused warming leads to catastrophic flooding in Texas.
Even shifting plates beneath the Earth’s crust (earthquakes) can be creatively connected to human-caused climate change.
Those who may dare to question the link between humanity’s growing oil, gas, and coal consumption and a weather or tectonic event are swiftly called “climate deniers,” and the substantive discussion that never happened (and was never going to happen) ends then and there.
In the 1970s, extreme weather events were blamed on global cooling
Interestingly, in the 1970s it was common for severe weather anomalies (for example, the deadly catastrophic drought plodding throughout the continent of Africa) to be linked to the global cooling occurring at that time. In 1974, NOAA acknowledged that many climate scientists had linked the drought and other extreme weather anomalies to the -0.5°C drop in temperatures that had occurred from the 1940s to 1970s.
“In the Sahelian zone of Africa south of the Sahara, the countries of Chad, The Gambia, Mali, Mauritania, Niger, Senegal, and Upper Volta are enduring a drought that in some areas has been going on for more than six years now, following some 40 previous years of abundant monsoon rainfall. And the drought is spreading—eastward into Ehtiopia and southward into Dahomey, Egypt, Guinea, Kenya, Nigeria, Somalia, Tanzania, and Zaire. … Many climatologists have associated this drought and other recent weather anomalies with a global cooling trend and changes in atmospheric circulation which, if prolonged, pose serious threats to major food-producing regions of the world. … Annual average temperatures over the Northern Hemisphere increased rather dramatically from about 1890 through 1940, but have been falling ever since. The total change has averaged about one-half degree Centigrade, with the greatest cooling in higher latitudes. A drop of only one or two degrees Centigrade in the annual average temperature at higher latitudes can shorten the growing season so that some crops have to be abandoned. … [T]he average growing season in England is already two weeks shorter than it was before 1950. Since the late 1950’s, Iceland’s hay crop yield has dropped about 25 percent, while pack ice in waters around Iceland and Greenland ports is becoming the hazard to navigation it was during the 17th and 18th centuries. … Some climatologists think that if the current cooling trend continues, drought will occur more frequently in India—indeed, through much of Asia, the world’s hungriest continent. … Some climatologists think that the present cooling trend may be the start of a slide into another period of major glaciation, popularly called an “ice age.”
But, like now, there were still a collection of scientists willing to reconsider the common-knowledge “beliefs” of the time. For example, Boer and Higuchi (1980) investigated the “belief” that more extreme climate variability accrued as temperatures cooled, concluding that the climate had not undergone significantly more extreme shifts in weather patterns and events during the mid-20th century global cooling period.
“In recent years there has been increasing concern about climatic change and variability and its influence on man and his activities. This concern has been formally expressed in a WMO statement on climate change and variability (WMO, 1976). Many studies concerning climate change have been undertaken. Most studies have concentrated on long-term trends in temperature. … There appears to be a general belief that the climate has become more “variable” in recent times. For instance, there is the suggestion that “since the 1940’s and 1950’s . . . the atmospheric circulation in the Northern Hemisphere appears to have shifted in a manner suggestive of an increasing amplitude of the planetary waves and of greater extremes of weather conditions in many areas of the world” (GARP, 1975, p. 16). … The results of this study do not support the contention that the climate has become significantly more variable, nor do they support a connection between variability and either mean temperature or north-south variation of temperature.”
Modern scientists also question the assumption that more warming means more variability
Likewise, today’s peer-reviewed scientific literature is teeming with examples of scientists who don’t appear acquiesce to the humans-cause-more-extreme weather-and-climate-events alarmism.
What follows below is a compilation of scientific papers published within the last year that do not support the popular contention that the Earth’s climate and weather (and seismic activity) have become more variable and more extreme in recent decades, or that warmer temperatures are necessarily associated with more variability and potential catastrophe. Instead, these papers indicate that the modern (20th, 21st century) climate is, and has been, remarkably stable, with significantly less extreme variability than in previous centuries and millennia.
For example, the scientific literature reveals natural global-scale climate warmings of multiple degrees per decade routinely occurred in the recent past. Greenland typically warmed at amplitudes of about 10.0°C in a matter of about 40 years during the last glacial — while CO2 levels remained stable and low (180 ppm) throughout. In contrast, the IPCC has concluded that the Earth has warmed at a rate of about 0.05°C per decade since 1850, or while CO2 levels have risen from 280 ppm to 400 ppm.
Scientists have also found the frequencies of storms and tsunamis have decreased during the 20th, 21st centuries; the frequencies and intensities of hurricanes have decreased in the last several decades; and there are far fewer wildfires today than centuries ago. Furthermore, scientists have found no significant trends (even decreases) in extreme precipitation events in recent decades compared to past centuries; drought frequencies and intensities are stable or decreasing; tornado occurrence has remained stable or decreased since 1950; climate models are too “unreliable” to simulate variability or extremes in weather patterns; and a warming climate is a more stable climate.
In other words, these papers do not support the popular assumption that just about every adverse weather event can be linked to global warming in general, or human activity in particular.
More weather instability/extremes, much higher climate change rates in cold periods than warm periods
“The demonstration using Greenland ice cores that abrupt shifts in climate [i.e. warming amplitudes of full degrees C per decade], Dansgaard-Oeschger (D-O) events, existed during the last glacial period has had a transformational impact on our understanding of climate change in the naturally forced world. The demonstration that D-O events are globally distributed and that they operated during previous glacial periods has led to extensive research into the relative hemispheric timing and causes of these events. The emergence of civilization during our current interglacial, the Holocene, has been attributed to the “relative climate quiescence” of this [warm] period relative to the massive, abrupt shifts in climate that characterized glacial periods in the form of D-O events“
“Many northern hemisphere climate records, particularly those from around the North Atlantic, show a series of rapid climate changes that recurred on centennial to millennial timescales throughout most of the last glacial period. These Dansgaard-Oeschger (D-O) sequences are observed most prominently in Greenland ice cores, although they have a global signature, including an out of phase Antarctic signal. They consist of warming jumps of order 10°C, occurring in typically 40 years, followed generally by a slow cooling (Greenland Interstadial, GI) lasting between a few centuries and a few millennia, and then a final rapid temperature drop into a cold Greenland Stadial (GS) that lasts for a similar period. … [S]teady changes in ice-sheet runoff, driven by the AMOC, lead to a naturally arising oscillator, in which the rapid warmings come about because the Arctic Ocean is starved of freshwater. The changing size of the ice sheets would have affected the magnitude and extent of runoff, and we suggest that this could provide a simple explanation for the absence of the [abrupt climate change] events during [warm] interglacials and around the time of glacial maxima [coldest climates].”
“Extreme climate changes in the past Ice core records show that Greenland went through 25 extreme and abrupt climate changes during the last ice age some 20,000 to 70,000 years ago. In less than 50 years the air temperatures over Greenland could increase by 10 to 15 °C. However the warm periods were short; within a few centuries the frigid temperatures of the ice age returned. That kind of climate change would have been catastrophic for us today.”
“The climate in the North Atlantic Ocean during the Marine Isotope Stage 3 (MIS 3) —roughly between 80,000 years before present (B.P.) and 20,000 years B.P., within the last glacial period—is characterized by great instability, with opposing climate transitions including at least six colder Heinrich (H) events and fourteen warmer Dansgaard–Oeschger (D-O) events. … During the D-O events, the high-latitude warming occurred abruptly (probably in decades to centuries), reaching temperatures close to interglacial conditions. Even though H and D-O events seemed to have been initiated in the North Atlantic Ocean, they had a global footprint. Global climate anomalies were consistent with a slowdown of AMOC and reduced ocean heat transport into the northern high latitudes.”
“The highest dust fluxes in the Baie bog were recorded from 1750–1000 cal. BP to 600–100 cal. BP and occur at the same time as periods of high variability in the macrofossil record (i.e. successive layers dominated by Sphagnum or Ericaceae). The timing of these events in the dust and macrofossil records also corresponds to documented cold periods. These two periods have been identified as episodes of climatic instability, which could have been caused by changes in the wind regime.”
“A comparison with North Atlantic and Western Mediterranean paleoclimate proxies shows that the phases of high storm activity occurred during cold periods, suggesting a climatically-controlled mechanism for the occurrence of these storm periods. Besides, an in-phase storm activity pattern is found between the Western Mediterranean and Northern Europe. Spectral analyses performed on the Sr content revealed a new 270-year solar-driven pattern of storm cyclicity. For the last 3000 years, this 270-year cycle defines a succession of ten major storm periods (SP) with a mean duration of 96 ± 54 yr. Periods of higher storm activity are recorded from >680 to 560 cal yr BC (SP10, end of the Iron Age Cold Period), from 140 to 820 cal yr AD (SP7 to SP5) with a climax of storminess between 400 and 800 cal yr AD (Dark Ages Cold Period), and from 1230 to >1800 cal yr AD (SP3 to SP1, Little Ice Age). Periods of low storm activity occurred from 560 cal yr BC to 140 cal yr AD (SP9 and SP8, Roman Warm Period) and from 820 to 1230 cal yr AD (SP4, Medieval Warm Period).”
Frequencies of storms and tsunamis have decreased during the 20th, 21st centuries
“Storms and tsunamis, which may seriously endanger human society, are amongst the most devastating marine catastrophes that can occur in coastal areas. Many such events are known and have been reported for the Mediterranean, a region where high-frequency occurrences of these extreme events coincides with some of the most densely populated coastal areas in the world. In a sediment core from the Mar Menor (SE Spain), we discovered eight coarse-grained layers which document marine incursions during periods of intense storm activity or tsunami events. Based on radiocarbon dating, these extreme events occurred around 5250, 4000, 3600, 3010, 2300, 1350, 650, and 80 years cal BP. No comparable events have been observed during the 20th and 21st centuries. The results indicate little likelihood of a tsunami origin for these coarse-grained layers, although historical tsunami events are recorded in this region. These periods of surge events seem to coincide with the coldest periods in Europe during the late Holocene, suggesting a control by a climatic mechanism for periods of increased storm activity.”
Frequencies and intensities of hurricanes have decreased
“Extratropical cyclones cause much of the high impact weather over the mid-latitudes. With increasing greenhouse gases, enhanced high-latitude warming will lead to weaker cyclone activity. Here we show that between 1979 and 2014, the number of strong cyclones in Northern Hemisphere in summer has decreased at a rate of 4% per decade, with even larger decrease found near northeastern North America. Climate models project a decrease in summer cyclone activity, but the observed decreasing rate is near the fastest projected. Decrease in summer cyclone activity will lead to decrease in cloud cover, giving rise to higher maximum temperature, potentially enhancing the increase in maximum temperature by 0.5 K or more over some regions. We also show that climate models may have biases in simulating the positive relationship between cyclone activity and cloud cover, potentially under-estimating the impacts of cyclone decrease on accentuating the future increase in maximum temperature.”
“Bayesian age–depth models, derived from eight AMS radiocarbon dates, suggest that the frequency of typhoon strikes was 2–5 times greater from 3900 to 7800 cal. yr. BP compared to 0–3900 cal. yr. BP. Possible explanations for this variability in the typhoon record are that typhoons were more frequent and/or more intense in Southeast Asia in the mid-Holocene because of climatic changes associated with the Mid-Holocene Warm Period or that the record reflects site sensitivity changes resulting from a mid-Holocene sea-level highstand.”
More tropical cyclones in a cooler climate?
“Recent review papers reported that many high-resolution global climate models consistently projected a reduction of global tropical cyclone (TC) frequency in a future warmer climate, although the mechanism of the reduction is not yet fully understood. Here we present a result of 4K-cooler climate experiment. The global TC frequency significantly increases in the 4K-cooler climate compared to the present climate. This is consistent with a significant decrease in TC frequency in the 4K-warmer climate.”
Fewer wildfires today than centuries ago
“Wildfire has been an important process affecting the Earth’s surface and atmosphere for over 350 million years and human societies have coexisted with fire since their emergence. Yet many consider wildfire as an accelerating problem, with widely held perceptions both in the media and scientific papers of increasing fire occurrence, severity and resulting losses. However, important exceptions aside, the quantitative evidence available does not support these perceived overall trends. Instead, global area burned appears to have overall declined over past decades, and there is increasing evidence that there is less fire in the global landscape today than centuries ago. Regarding fire severity, limited data are available. For the western USA, they indicate little change overall, and also that area burned at high severity has overall declined compared to pre-European settlement. Direct fatalities from fire and economic losses also show no clear trends over the past three decades.”
No trends (decreases) in extreme precipitation events in recent decades compared to past centuries
“The reconstruction shows that significantly longer and more frequent wet and dry periods were experienced in the preinstrumental [19th century and earlier] compared to the instrumental period [20th, 21st centuries]. This suggests that existing drought and flood risk assessments underestimate the true risks due to the reliance on data and statistics obtained from only the instrumental record.”
“Following the devastating droughts that ravaged the Sahel in the 1970–1980s, many efforts have been directed at investigating climate variability in Northern Africa, focusing on vegetation–climate feedbacks and the dynamics of the West African Monsoon (WAM) system (Charney et al., 1975 and Giannini et al., 2003). However, the past millennia have witnessed much larger precipitation changes than those seen in recent decades. One of the most dramatic changes in the WAM began around 15000 yr BP, when increased summer precipitation led to an expansion of the North African lakes and wetlands.”
Changes in annual precipitation over the Earth’s land mass excluding Antarctica from the 18th century to 2013
“The trends for precipitation change together with their 95% confidence intervals were found for various periods of time. Most trends exhibited no clear precipitation change [from the 1700s to present]. The global changes in precipitation over the Earth’s land mass excluding Antarctica relative to 1961-90 were estimated to be: -1.2. ±. 1.7, 2.6. ±. 2.5 and -5.4. ±. 8.1% per century for the periods 1850-2000, 1900-2000 and 1950-2000, respectively. A change of 1% per century corresponds to a precipitation change of 0.09. mm/year.”
“We developed the first boreal spring precipitation reconstruction for the western Himalaya covering the last millennium (1030–2011 C.E.). … The precipitation reconstruction revealed persistent long-term spring droughts from the 12th to early 16th century C.E. and pluvial from the late 16th century C.E. to recent decades. The late 15th and early 16th centuries (1490–1514 C.E.) displayed the driest episode, with precipitation being ∼15% lower than the long-term mean. The early 19th century (1820–1844 C.E.) was the wettest period of the past millennium, with mean precipitation ∼13% above the long-term mean. The reconstructed boreal spring precipitation from the western Himalaya revealed large-scale consistency with hydrological records from westerly dominated regions in Central Asia, indicating synoptic-scale changes in atmospheric circulation during the major part of the Medieval and Little Ice Age periods.”
“Time series of US daily heavy precipitation (95th percentile) are analyzed to determine factors responsible for regionality and seasonality in their 1979-2013 trends. …. Analysis of model ensemble spread reveals that appreciable 35-yr trends in heavy daily precipitation can occur in the absence of forcing, thereby limiting detection of the weak anthropogenic influence at regional scales.
Analysis of the seasonality in heavy daily precipitation trends supports physical arguments that their changes during 1979-2013 have been intimately linked to internal decadal ocean variability, and less to human-induced climate change.”
“[T]he observed record and historical model experiments were used to investigate changes in the recent past. In part because of large intrinsic variability, no evidence was found for changes in extreme precipitation attributable to climate change in the available observed record“
Drought frequencies and intensities are stable, decreasing
“The results thus indicate that the net effect of climate change has made agricultural drought less likely and that the current severe impacts of drought on California’s agriculture have not been substantially caused by long-term climate changes.”
Abrupt mid-Holocene megadrought in northwestern Montana
“One of the best studied examples of historic drought in North America includes the 1930s Dust Bowl event (Woodhouse and Overpeck, 1998) that heavily impacted agriculture in the Great Plains region and that is well represented in lake sediment records in North America (e.g. Alley et al., 2003). Interestingly, lake sediment records that contain a signal of the Dust Bowl event (e.g. Alley et al., 2003) also show that such events occurred more frequently and on a higher magnitude throughout the late Holocene (Laird et al., 1996).”
“Nationwide drought is predicted to become more common with anthropogenic climate change, but the MXDA reconstructions indicate that intense “All Mexico” droughts have been rare over the past 600 years and their frequency does not appear to have increased substantially in recent decades.”
“How drought may change in the future are of great concern as global warming continues. In Part I of this study, we examine the uncertainties in estimating recent drought changes. … Consistent with reported declines in pan evaporation, our calculated potential evapotranspiration (PET) shows negative or small trends since 1950 over the United States, China, and other regions, and no global PET trends from 1950 to 1990. Updated precipitation and streamflow data and the self-calibrated PDSI_pm all show consistent drying during 1950–2012 over most Africa, East and South Asia, southern Europe, eastern Australia, and many parts of the Americas. While these regional drying trends resulted primarily from precipitation changes related to multi-decadal oscillations in Pacific sea surface temperatures, rapid surface warming and associated increases in surface vapor pressure deficit since the 1980s have become an increasingly important cause of widespread drying over land.”
Tornado occurrence has remained stable since 1950
Variability of Tornado Occurrence over the Continental United States since 1950
“The United States experiences the most tornadoes of any country in the world. Given the catastrophic impact of tornadoes, concern has arisen regarding the variation in climatology of U.S. tornadoes under the changing climate. … Based on the 64-year tornado records (1950-2013), we found that the trends in tornado temporal variability varied across the U.S., with only one-third of the continental area or three out of ten contiguous states (mostly from the Great Plains and Southeast, but where the frequency of occurrence of tornadoes is greater) displaying a significantly increasing trend. The other two-thirds area, where 60% of the U.S. tornadoes were reported (but the frequency of occurrence of tornadoes is less), however, showed a decreasing or a near-zero trend in tornado temporal variability. Furthermore, unlike the temporal variability alone, the combined spatial-temporal variability of U.S. tornado occurrence has remained nearly constant since 1950.”
Unreliable climate models do not simulate variability or extremes – warming stabilizes the climate
Attribution of extreme weather and climate events overestimated by unreliable climate simulations
“The framework illustrates that unreliable climate simulations are prone to overestimate the attributable risk to climate change. Climate model ensembles tend to be overconfident in their representation of the climate variability which leads to systematic increase in the attributable risk to an extreme event. Our results suggest that event attribution approaches comprising of a single climate model would benefit from ensemble calibration in order to account for model inadequacies similarly as operational forecasting systems.”
“[T]he intensification of the twentieth-century-mean hydroclimate anomalies in the simulations, as compared to previous centuries, is not supported by our new multi-proxy reconstruction. This finding suggests that much work remains before we can model hydroclimate variability accurately, and highlights the importance of using palaeoclimate data to place recent and predicted hydroclimate changes in a millennium-long context.”
According to a new study, the Northern Hemisphere has experienced considerably larger variations in precipitation during the past twelve centuries than in the twentieth century. Researchers from Sweden, Germany, and Switzerland have found that climate models overestimated the increase in wet and dry extremes as temperatures increased during the twentieth century.
“‘Tipping points’ (TPs) are thresholds of potentially disproportionate changes in the Earth’s climate system associated with future global warming and are considered today as a ‘hot’ topic in environmental sciences. In this study, TP interactions are analysed from an integrated and conceptual point of view using two qualitative Boolean models built on graph grammars. They allow an accurate study of the node TP interactions previously identified by expert elicitation and take into account a range of various large-scale climate processes potentially able to trigger, alone or jointly, instability in the global climate. Our findings show that, contrary to commonly held beliefs, far from causing runaway changes in the Earth’s climate, such as self-acceleration due to additive positive feedbacks, successive perturbations might actually lead to its stabilization.”
“Substantial changes in the hydrological cycle are projected for the 21st century, but these projections are subject to major uncertainties. In this context, the ‘dry gets drier, wet gets wetter’ (DDWW) paradigm is often used as a simplifying summary. However, recent studies cast doubt on the validity of the paradigm and also on applying the widely used P-E (precipitation-evapotranspiration) metric over global land surfaces. Here we show in a comprehensive CMIP5-based assessment that projected changes in mean annual P-E are generally not significant, except for high-latitude regions showing wetting conditions until the end of the 21st century. Significant increases in aridity do occur in many subtropical, but also adjacent humid regions. However, combining both metrics still shows that ca. 70% of all land area will not experience significant changes. Based on these findings we conclude that the DDWW paradigm is generally not confirmed for projected changes in most land areas.”