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THIS POST IS A CRITICAL REVIEW OF AN ONLINE PRESENTATION BY NASA [LINK] ON AGW CLIMATE CHANGE THAT NASA SAYS PRESENTS THE EVIDENCE IN TERMS OF “VITAL SIGNS OF THE PLANET” AND THE ANSWER TO THE QUESTION “HOW DO WE KNOW?” IT IS PRESENTED AS A SERIES OF CLAIMS MADE BY NASA WITH A CRITICAL RESPONSE TO EACH CLAIM.

CLAIM#1:  The abrupt end of the last ice age about 11,700 years ago marking the beginning of the modern climate era and of human civilization. RESPONSE#1: The general view in paleo climatology is that a chaotic deglaciation from the last glacial maximum began about 20,000 years ago but with a violent return to icy conditions in the Younger Dryas event about 12,000 years ago or so that eventually settled down to a the warm conditions of the Holocene Climate Optimum (HCO) [LINK] at some time between 7,000 to 5,000 years ago. It was then that the wild cave dwelling hunter-gatherer animal-like humans came out of their forest caves, cut down forests, built homes, and began to farm and raise farm animals. These settlements also created communities and other advances that gave us human civilization. Since then, what we see in the paleo record are chaotic cycles of warming and cooling at millennial and centennial time scales described in a related post [LINK] . The last three such cycles are the Medieval Warm Period (MWP) [LINK] , the Little Ice Age (LIA), and the current warm period described as anthropogenic global warming (AGW). It is therefore not possible to combine the very different climatic conditions in the period 11,700 years ago to the present in terms of a single climatic condition that can be described as “the modern climate era”. The reference to “human civilization” as early as 11,700 years ago, is equally mysterious since the Neolithic Revolution came much later. Also, the use of the phrase “modern climate era” to refer to deglaciation and the climate cycles of the Holocene can create confusion because the same phrase is also used to refer to the current warm period that followed the LIA.

CLAIM#2:  The current warming trend is of particular significance because most of it is extremely likely (greater than 95 percent probability) to be the result of human activity since the mid-20th century and proceeding at a rate that is unprecedented over decades to millennia. Earth-orbiting satellites and other technological advances have enabled scientists to see the big picture, collecting many different types of information about our planet and its climate on a global scale. This body of data, collected over many years, reveals the signals of a changing climate.  RESPONSE#2A:  In climate science from Callendar (1938) [LINK] to IPCC (2018), the human activity that causes warming is specified as fossil fuel emissions of the industrial economy and not human activity in general as suggested in the NASA text. The period over which human fossil fuel emissions have been causing warming is described as “since pre-industrial” such that the amount of warming caused by human fossil fuel emissions is computed as the difference between the current temperature and the reference pre-industrial temperature. However, there seems to be some confusion as to the reference “pre-industrial” year from which to compute the amount of warming. Callendar (1938), the world’s first AGW climate change paper, set the reference pre-industrial time to the year 1900. Since then this reference has varied. The IPCC 2001 & 2007 reports set the pre-industrial times to the year 1750 as the time when humans burning fossil fuels caused the LIA to end and to flip the LIA cooling trend to the AGW warming trend. However, in their 2015 and later reports, the IPCC changed the pre-industrial reference year to 1850. More recently, climate scientist James Hansen changed the reference pre-industrial year to 1950 saying “that “in the 30-year period 1950-1980 there is a strong measurable warming rate with 99% probability for human cause” and NASA followed suit saying that “AGW started in 1950 because from then the relationship between CO2 and temperature we see in the climate models closely matches the observational data. This exact argument has also been put forward by climate scientist Peter Cox but with the reference pre-industrial year set to “the 1970s”. The importance of the amount of warming since pre-industrial is claimed to be crucial by the IPCC and by climate science in the planning and execution of climate action to limit and eventually eliminate fossil fuel emissions to moderate the rate of AGW before it reaches a critical value of the amount of warming since pre-industrial”. However, the uncertainty in when to mark the “pre-industrial” reference interferes with this line of climate action reasoning and climate action planning. Climate action plans include the critical variable that specifies the amount of warming since pre-industrial that must not be crossed to avoid a complete collapse of the climate system and irreversible climate change. Currently that critical amount of warming since pre-industrial is thought to be 1.5C proposed in the 2018 IPCC special report. Prior to that it was specified as 2C in the 2015 IPCC report, 3C in 2013, 4C in 2007, and 5C in 2001. It appear that scientists in charge of saving us from climate breakdown and irreversible climate change by limiting warming are unsure when to begin the warming accounting and exactly how much warming to target.  RESPONSE#2B:  It is noted that the determination of the reference year for when AGW began, Hansen, Cox, and NASA deduced their hypotheses from the data as in “the 30-year period 1950-1980 there is a strong measurable warming rate with 99% probability for human cause”, and then tested the hypothesis with the same data. This kind of hypothesis test contains  the circular reasoning fallacy also known as the Texas Sharpshooter Fallacy [LINK] . This kind of reasoning does not provide acceptable hypothesis tests that can be accepted as evidence. The NASA, Hansen, and Cox findings of when AGW began are rejected on this basis.

CLAIM#3:  The heat-trapping nature of carbon dioxide and other gases was demonstrated in the mid-19th century. Their ability to affect the transfer of infrared energy through the atmosphere is the scientific basis of many instruments flown by NASA. There is no question that increased levels of greenhouse gases must cause the Earth to warm in response. Ice cores drawn from Greenland, Antarctica, and tropical mountain glaciers show that the Earth’s climate responds to changes in greenhouse gas levels. Ancient evidence can also be found in tree rings, ocean sediments, coral reefs, and layers of sedimentary rocks. This ancient, or paleoclimate, evidence reveals that current warming is occurring roughly ten times faster than the average rate of ice-age-recovery warming.  RESPONSE#3:  There may be no question that increased levels of greenhouse gases cause the earth to warm in response but the real issue in terms of the call to climate action and of formulating climate action plans is not whether it causes warming but how much. That question is answered by the climate sensitivity parameter, an unsettled issue in climate science because the range of values reported in the literature is so large that the concept is rendered meaningless. It is possibly the frustration of climate science with with the climate sensitivity issue that drove them to the TCRE (Transient Climate Response to Cumulative Emissions) that is now used to construct carbon budgets for climate action plans. There is no direct measure of the “heat-trapping nature of carbon dioxide” in this simple model that relates warming to emissions as 1C to 2.5C of warming for each teratonne of cumulative fossil fuel emissions. The TCRE is now used to construct climate action plans in terms of carbon budgets for any given warming target. An unresolved issue in this regard is the so called “remaining budget” described in a related post [LINK] where we find that the mystery of the remaining budget problem is that the TCRE is based on a spurious correlation that has no interpretation in terms of the real world phenomena it appears to represent [LINK] .

CLAIM#4:   For millennia, atmospheric carbon dioxide had never been above 300 ppm, but since 1950 it has shot up to well above 420 ppm.  RESPONSE#4A:  A common theme in NASA’s view of climate science is that extreme values prove human cause as in look how warm it is, or look how fast it is warming, or look how high the CO2 is and so on and so forth. Yet extreme values do not prove human cause and the fall back to this illogical and unscientific argument implies that all is not right in climate science or perhaps all is not right in the rocket science world of NASA. RESPONSE#4B:  The other issue with this repeated and high profile claim by NASA, that 420 ppm CO2 is unprecedented for millions of years, is that in the first millennium of the previous interglacial, the Eemian [LINK] , about 125,000 years ago or so, it was much warmer than today presumably at less than 300 ppm as implied by NASA’s “unprecedented” claim. Therefore, if NASA is right about the CO2 history it is wrong about the CO2 interpretation of warming.

CLAIM#5:  Ancient evidence can also be found in tree rings, ocean sediments, coral reefs, and layers of sedimentary rocks. This ancient, or paleoclimate, evidence reveals that current warming is occurring roughly ten times faster than the average rate of ice-age-recovery warming.   RESPONSE#5A:  Here again NASA is using large values compared with history to imply that “unprecedented” proves human cause. It does not. Unprecedented only proves unprecedented. It may lead to suspicions of and hypotheses for what may have caused such an anomalous value but these hypotheses must be put through rigorous hypothesis tests with the null hypothesis that it is false. “unprecedented” in and of itself does not prove human cause. RESPONSE#5B:  Why is a single interglacial event, claimed to be unprecedented, being compared with an average instead of the the set of all prior extreme events in the paleo record? Once again, if we compare the Holocene to the previous interglacial, the Eemian, we find in the Eemian a much more violent deglaciation, much faster warming, and higher temperature in the first millennium of the interglacial compared with the relatively mild Holocene [LINK] .  RESPONSE#5C:  It should also be noted that the issue is the current warming period that followed the Little Ice Age more than 10 millennia into the Holocene interglacial. This recovery from the Little Ice Age is not “ice age recovery warming”. Yes, the LIA is indeed called the Little “Ice Age” but it was not a glaciation as in the Pleistocene but just a hundred years or so of harsh cold weather that caused great hardship in Europe [LINK] .

CLAIM#6:  The planet’s average surface temperature has risen about 0.9C since the late 19th century, a change driven largely by increased carbon dioxide and other human-made emissions into the atmosphere. Most of the warming occurred in the past 35 years, with the five warmest years on record taking place since 2010. Not only was 2016 the warmest year on record, but eight of the 12 months that make up the year — from January through September, with the exception of June — were the warmest on record for those respective months.  RESPONSE#6A:  In claim#2 above, NASA says that the current period of human caused global warming and climate change began in 1950; but down here in claim#6 the current period of human caused global warming is computed from “the late 19th century”. Such inconsistencies and contradictions need to be clelaned up if a credible case for climate action against fossil fuel is to be presented to taxpayers and governments.  RESPONSE#6B:  The claim that the warming is “driven largely by increased carbon dioxide and other human-made emissions into the atmosphere” is inconsistent with the theory of AGW as initially proposed from Callendar 1938 to Hansen (1981, 1988), Lacis (2010), and by NASA itself [LINK] . The very essence of the theory of AGW climate change is that it is a creation of the industrial economy in the form of the carbon in fossil fuels that is millions of years old such that it does not belong in the current account of the carbon cycle; and that therefore the injection of this old external carbon of the industrial economy into the current account of the carbon cycle is a perturbation of nature’s delicately balanced carbon cycle and climate system that it is deemed to be human caused. It should be noted that this strict definition of human cause by way of the industrial economy is still used in the TCRE (Transient Climate Response to Cumulative Emissions) and in the construction of the carbon budgets for climate action plans. The need to interject “and other human-made emissions” into AGW theory is mysterious and may imply that there are unresolved issues in the theory as originally proposed [LINK] . RESPONSE#6C:  The various claims of extreme temperature events {the five warmest years on record taking place since 2010. Not only was 2016 the warmest year on record, but eight of the 12 months that make up the year from January through September, with the exception of June were the warmest on record for those respective months}  have no interpretation as empirical evidence for a theory, not about temperature events, but about long term trends in temperature. The issue here is climate sensitivity. The WMO says that only warming trends serve as evidence in this regard and that the trends should be assessed for periods of 30 years or longer. In climate sensitivity research climate scientists have claimed that the slower ocean response may mean that the period over which AGW warming must be assessed is longer by factors of two or three. What is the role of extreme temperature events in this context? A somewhat related issue is that the use of extreme El Nino events like 2016 as evidence of AGW may indicate a deception strategy to sell climate alarm and push the climate action agenda of anti fossil fuel activism that has corrupted climate science [LINK] .

CLAIM#7:  The oceans have absorbed much of this increased heat, with the top 700 meters (about 2,300 feet) of ocean showing warming of more than 0.4 degrees Fahrenheit since 1969.  RESPONSE#7A:  The need to insert the Fahrenheit scale as needed is an oddity that is best understood as climate activism and not as science. Perhaps 0.22C does not sound as alarming as 0.4F. That rocket scientists at NASA would stoop to such tactics to sell fear of AGW does not speak well for the substance of the case against fossil fuels.  RESPONSE#7B:  Ocean heat content (OHC) dynamics cannot be understood purely in terms of atmospheric phenomena because of known geothermal heat sources in the ocean that far exceed AGW driven warmth created in the atmosphere. An added consideration is that atmosphere driven ocean warming would be more uniform than what the data shows. What we see in the data down to 700 meters is a distribution of ocean heat content dynamics that is localized and not uniform [LINK] .  At 700M the OHC is in decline in the North Pacific at a rate of 0.29E22 JPY (Joules per year) and in the South Pacific and at a rate of 0.25E22 JPY; and OHC increase is seen in the North Pacific at 0.32E22 JPY and the South Indian Ocean at 0.30E22 JPY. A state of incongruity in OHC trends according to location implies that significant geological sources of heat known to exist in the ocean must also be considered. These conclusions are supported by similar works carried out by James Edward Kamis and Robert Stevenson. See also the Wyss paper  [ wyss episodic geothermal ] and the recently published Zanna et al 2018 [LINK] .

CLAIM#8:  The Greenland and Antarctic ice sheets have decreased in mass. Data from NASA’s Gravity Recovery and Climate Experiment show Greenland lost an average of 286 billion tons of ice per year between 1993 and 2016, while Antarctica lost about 127 billion tons of ice per year during the same time period. The rate of Antarctica ice mass loss has tripled in the last decade. Glaciers are retreating almost everywhere around the world — including in the Alps, Himalayas, Andes, Rockies, Alaska and Africa. Satellite observations reveal that the amount of spring snow cover in the Northern Hemisphere has decreased over the past five decades and that the snow is melting earlier. RESPONSE#8:  Glacial retreat and reductions in polar ice sheet mass are the norm in interglacials and not an oddity of the post LIA warming that requires an explanation in terms of human cause. In the prior interglacial, the Eemian, the Greenland Ice Sheet had shrunk to a size much smaller than it is today and the West Antarctic Ice Sheet had disintegrated only a millennium into the interglacial. In this context, it does not appear that polar ice sheet mass losses found more than ten millennia into the Holocene is an unusual event that requires an explanation in terms of the industrial economy and human cause.

CLAIM#9: Global sea level rose about 8 inches in the last century. The rate in the last two decades, however, is nearly double that of the last century and is accelerating slightly every year.  RESPONSE#9: Sea level rise is the norm in interglacials and acceleration in the rate of sea level rise is normal during warming periods of interglacials. For example, in the first millennia of the Eemian, the previous interglacial, sea levels rose much higher and with much greater acceleration that what is seen in the post LIA warming of the Holocene [LINK] . It should also be mentioned that we are now more than ten millennia into the Holocene interglacial and the paleo data show that these ten millennia did not progress as smoothly as what climate science must assume about how interglacial climate behaves without human cause. What they show instead is a sequence of violent and chaotic cycles of warming and cooling at millennial and centennial time scales with glacial retreat, ice melt, and sea level rise in the warming cycles and glacial advance in the cooling cycles [LINK] . That the sea level is also rising in this warming episode is not an unnatural thing in light of the history of the Holocene and it does not require an explanation in terms of human cause and the industrial economy.

CLAIM#9: Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades. RESPONSE#9: The data for sea ice volume contains both measures mentioned, namely extent and thickness. The PIOMAS ice volume data for Arctic sea ice does indeed  show a decline over a period of four decades 1979-2019. However, the assumption that this decline is human caused by way of the industrial economy and that it can be halted by taking climate action is not supported by the data. The absence of evidence that Arctic sea ice volume is responsive to AGW surface temperature shown in a related post [LINK] does not support the human cause assumption. As a footnote, assumptions of this nature are characteristic of climate science and they imply that in climate science the hypothesis testing logic has been inverted. The scientific method requires that in empirical tests of theory, the null hypothesis should be the absence of the proposed effect such that only its statistically significant rejection can lead to a verification of the effect. However, in climate science, the effect is subsumed in emprical tests such that it serves as the null hypothesis. 

CLAIM#10: Since the beginning of the Industrial Revolution, the acidity of surface ocean waters has increased by about 30 percent. This increase is the result of humans emitting more carbon dioxide into the atmosphere and hence more being absorbed into the oceans. The amount of carbon dioxide absorbed by the upper layer of the oceans is increasing by about 2 billion tons per year. RESPONSE#10: It is shown in a related post [LINK] that the data do not support the assumed atmospheric cause of ocean acidification by way of fossil fuel emissions. Correlation analysis does not show that the rate of ocean acidification is responsive to fossil fuel emissions and a mass balance analysis does not show that there is enough carbon in fossil fuel emissions to explain the observed changes in the ocean [LINK] .  Therefore, the real cause of these changes must lie in the ocean itself. Unbiased and objective scientific inquiry should include the role of submarine geological activity in the investigation of ocean acidification and it is implied by the data. A salient example of ocean acidification in the paleo record is the PETM (Paleocene Eocene Thermal Maximum) event that involved catastrophic ocean acidification by the ocean itself. This event is described in a related post [LINK] . 

CLAIM#11: Vital Signs of the Planet.RESPONSE#11:  The crust of the planet where we have land, ocean, atmosphere, ice sheets, glaciers, glaciation cycles, interglacials, climate, living creatures, and humans is 0.3% of the planet containing 0.2% of the planet’s carbon. The other 99.7% of the planet and 99.8% of its carbon are in the core and mantle of the planet where there is no atmosphere, no climate, no ice sheets, no glaciation cycles, no interglacials, no living creatures, and no humans. The passion and obsession of climate science to describe the post LIA current warming period of the Holocene interglacial in planetary terms exposes activist and alarmist underpinnings of climate science and that in turn does not support the claim of climate science to scientific legitimacy. 

CLAIM#12: The number of record high temperature events in the United States has been increasing, while the number of record low temperature events has been decreasing, since 1950. The U.S. has also witnessed increasing numbers of intense rainfall events. RESPONSE#12:  As noted above, temperature events have no interpretation in terms of a theory about long term warming trends caused by the heat trapping effect of rising atmospheric CO2 concentration. The irrelevance of such events is even more so when the temperatures are regional temperatures and not global mean temperatures.

POSTSCRIPT:  At the very foundation of AGW climate change theory is the assumption that atmospheric composition is responsive to fossil fuel emissions such that the observed rise in atmospheric CO2 concentration is explained by fossil fuel emissions and that therefore it can be moderated with climate action consisting of reducing and eventually eliminating the rate of fossil fuel emissions. In related posts it is shown that neither correlation analysis nor mass balance analysis supports this assumption. [LINK] [LINK] . Thus the very foundation of climate science has no empirical support.