FIGURE 1: GLACIATION EXTENT SINCE THE EEMIAN INTERGLACIAL

FIGURE 2: TEXAS SHARPSHOOTER FALLACY

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THE NASA STATEMENT THAT PROVES HUMAN CAUSED GLOBAL WARMING AND CLIMATE CHANGE SINCE PRE-INDUSTRIAL TIMES AS A DIRECT RESULT OF FOSSIL FUEL EMISSIONS.[LINK TO SOURCE DOCUMENT]

The Earth’s climate has changed throughout history. Just in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7,000 years ago marking the beginning of the modern climate era and of human civilization. Most of these climate changes are attributed to very small variations in Earth’s orbit that change the amount of solar energy our planet receives. Scientific evidence for warming of the climate system is unequivocal according to the Intergovernmental Panel on Climate Change. 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. The heat-trapping nature of carbon dioxide and other gases was demonstrated in the mid-19th century.2 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. The evidence for rapid climate change is compelling. Global temperature rise. The planet’s average surface temperature has risen about 2.0 degrees Fahrenheit (1.1 degrees Celsius) since the late 19th century. The planet’s average surface temperature has risen about 1.62 degrees Fahrenheit (0.9 degrees Celsius) 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. Warming oceans. 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. 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. Shrinking ice sheets:  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 281 billion tons of ice per year between 1993 and 2016, while Antarctica lost about 119 billion tons during the same time period. The rate of Antarctica ice mass loss has tripled in the last decade. Glacial retreat: Glaciers are retreating almost everywhere around the world including in the Alps, Himalayas, Andes, Rockies, Alaska and Africa. Decreased snow cover:  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. Sea level rise: 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. Maldives vulnerable to sea level rise. Declining Arctic sea ice: Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades. Extreme events: 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. Ocean acidification: 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.

COMMENTS

1. “The abrupt end of the last ice age about 7,000 years ago marking the beginning of the modern climate era and of human civilization”: The last ice age ended more than 2.5 billion years ago. Since then we have been in the Quaternary Ice Age marked by an intact Antarctic ice sheet for its duration. The ice age is punctuated by cycles of long periods of glaciation and brief periods of interglacial warmth. The Last Glacial Period ended about 11,700 years ago and initiated the Holocene warm period in which we live. As for human civilization, it got started with the Neolithic Revolution some 8,000 years ago. Not sure what the 7,000 year figure refers to in this context.
2. With reference to glaciation/interglacial cycles, NASA says “Most of these climate changes are attributed to very small variations in Earth’s orbit that change the amount of solar energy our planet receives“. This earth warming dynamic is the Milankovitch theory of glaciation cycles at 100,000-year time cycles . It has no relevance to the millennial millennial scale warming and cooling cycles of interglacials one of which is the issue under consideration.
3. Scientific evidence for warming of the climate system is unequivocal according to the Intergovernmental Panel on Climate Change. The IPCC is a UN committee charged with recommending climate change mitigation options to the United Nations. It is not a climate science organization and it does not carry out climate research. Therefore it is not a source of climate science information and can’t be cited to establish scientific evidence. Also, the use of words like “unequivocal” (leaving no doubt) is an unscientific attempt to discourage discussion on the substance of the issue.
4. 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. The theory of anthropogenic global warming (AGW) is that the rise in atmospheric CO2 concentration and the corresponding rise in temperature since pre-industrial times is due to fossil fuel emissions of the industrial economy. It is generally agreed that the demarcation between industrial times and pre-industrial times lies somewhere between 1850 and 1900. The theory should be tested in that time frame. To hunt and find a period of convenience where the data are more agreeable to theory is a form of circular reasoning and can be described as the Texas Sharpshooter Fallacy shown in Figure 2.
5. 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.  The argument has been made repeatedly by NASA that the rate of warming is unprecedented and that therefore it must have a human cause. This claim is flawed. Even if it were true, that the rate of warming is unprecedented does not prove human cause.
6. 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.  AGW serves as the rationale for an overhaul of the world’s energy infrastructure away from fossil fuels to renewable energy to reduce and eliminate fossil fuel emissions as a way of attenuating the rate of warming. That NASA satellites have seen signals of a changing climate does not address this central issue. That the climate is changing in one of more than eight violent warming and cooling cycles of the Holocene does not proves that it is human caused and that it can and must be attenuated by human intervention in the form of moving from fossil fuel energy to renewables.
7. The heat-trapping nature of carbon dioxide and other gases was demonstrated in the mid-19th century.  This statement is false. The works of Arrhenius, Hogbom, Tyndal, Langley, and others were a failed attempt to explain glaciation cycles over long periods at time scales of  around 100,000 years. That relationship was never demonstrated and it ultimately failed. Our current theory of glaciation cycles is that of Milankovitch that has to do with orbital anomalies and not carbon dioxide.
8. There is no question that increased levels of greenhouse gases must cause the Earth to warm in response.  There may be no question among climate scientists and NASA scientists and there is no question that it is found in climate models where it is programmed in, but “unequivocal” empirical evidence for this relationship has yet to be presented. More importantly, if NASA rocket scientists know the causation phenomena for the eight or more warming and cooling cycles of the Holocene we have endured so far, they should explain all of them and not pick one of them to explain. Please see: HOLOCENE TEMPERATURE CYCLES  
9. 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. With reference to the previous comment in item #8, if these relationships can explain Holocene warming and cooling cycles, NASA rocket scientists should be able to explain all of them and not just pick one to explain.
10. 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.  Only long term trends in temperature and not temperature events, however dramatic they may seem, may be used as evidence to support a warming climate. More to the point, the issue is not whether it is warming but whether the proposed overhaul of the world’s energy infrastructure away from fossil fuels and to renewable sources will produce the desired changes. It should also be mentioned that the year 2016 (like the year 1998 before it) is noted for a monster ENSO event and the high temperatures reported here should have been presented in that context. The omission of this piece of critical information in the presentation of 2016 temperatures is a form of scientific fraud.
11. 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. 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. What is the theoretical significance of the year 1969? If none, then its use is a form of circular reasoning and the Texas Sharpshooter fallacy. Also the observation that oceans have warmed in itself does not serve as evidence that the warming was caused by fossil fuel emissions and that it can be attenuated by cutting emissions; as explained in a related post [LINK] .
12. 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 281 billion tons of ice per year between 1993 and 2016, while Antarctica lost about 119 billion tons per year during the same time period. The rate of Antarctica ice mass loss has tripled in the last decade. The Greenland ice sheet is losing  0.0084% of its ice per year and at that rate will be gone in the next 11,000 to 12,000 years. Antarctica is losing 0.00045% of its ice per year and at that rate will be gone in 20,000 years or so. Although these statistics are cited by climate science as a evidence of anthropogenic global warming, no data or analysis is provided to discriminate the causation of ice melt in these geologically active areas between geothermal heat and anthropogenic global warming.  Related post on geological activity in the polar regions:  LINK TO POLAR ICE DYNAMICS  
13. Glaciers are retreating almost everywhere around the world including in the Alps, Himalayas, Andes, Rockies, Alaska and Africa. Decreased snow cover: 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. 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.  The only information in these changes is that we are in one of many Holocene warming periods. They do not require an explanation in terms of human cause.
14. 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. Maldives vulnerable to sea level rise. The only information in these changes is that we are in one of many Holocene warming periods. They do not require an explanation in terms of human cause.  That human activity in terms of fossil fuel emissions plays a role in these changes can only be established by showing a relationship between emissions and sea level rise such that the relationship has a causation interpretation. This was done in Peter Clark’s 2018 paper (Clark, Peter U., et al. “Sea-level commitment as a gauge for climate policy.” Nature Climate Change 8.8 (2018): 653) but the correlation used in the paper is spurious as shown in a related post [LINK] . When this statistical flaw in the paper is corrected no correlation between emissions and sea level rise remains as shown in another related post [LINK] . There is no evidence that these changes in this interglacial are abnormal and that climate action in the form of reducing or even eliminating fossil fuel emissions will moderate these changes.
15. Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades. Sea ice decline is also normal in interglacials. Human cause is not necessary to explain such phenomena in interglacials. A notable issue with sea ice in this interglacial is the difference between the Arctic where summer sea ice is declining and the Antarctic where it is not. This difference may imply a role for other causes of sea ice decline in the Arctic not considered or studied because of the obsession with human caused climate change. This issue is discussed more fully in a related post [LINK] .
16. 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. The issue here is long term trends in global mean temperature. Localized temperature events are constrained in time and geography and have no interpretation in terms of global warming. Please see: LINK TO INTERNAL CLIMATE VARIABILITY Extreme weather events happen anyway naturally without the use of fossil fuel emissions as seen in thousands of years of weather records kept by the Chinese government in the Fang-Zhi, in ancient Egyptian records, in the Late Bronze Age Collapse, and in the meticulous weather records of the British colonial government in India where devastating extreme weather events on record include the Bengal droughts of 1770, 1783, 1866, 1873, 1892, 1897, and 1943, the Calcutta cyclone of 1737, and lastly the Bhola cyclone that occurred during a time of global cooling in 1970. Therefore, the occurrence of droughts, floods, extreme storms, and heatwaves in this period of warming does not establish a causal connection to fossil fuel emissions. It  must be shown that there are long term trends related to fossil fuel emissions or that a distinction can be made in the aggregate events in the post industrial era compared with a corresponding pre-industrial era. No such evidence exists. In fact all studies of long term trends have failed to find a trend imposed by the use of fossil fuels in the post industrial era. See for example, the trend in tropical cyclones presented in a related post [LINK] . The only evidence presented is in terms of what is called “Event Attribution Science” where selected weather events are examined after the fact in climate models to compare the probability of the event in a world with fossil fuel emissions with that in a world without fossil fuel emissions and then to use the ratio of these probabilities to make a determination that that particular event was or was not caused by fossil fuel emissions. This procedure is derived from the so called “Warsaw International Mechanism” (WIM) devised by the United Nations for the allocation of climate change impact compensation funding to poor countries deemed “vulnerable” to climate change impacts. The elevation of this procedure to empirical evidence by giving it a different name that includes the word “science” does not make it science because climate models are an expression of theory and empirical evidence must be independent of theory to be free of circular reasoning and confirmation bias. Related Posts: [LINK] [LINK]
17. 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.  The statement that the increase in acidity “is the result of humans emitting more carbon dioxide into the atmosphere” requires empirical evidence. None is provided possibly because no such evidence exists. Kindly note that a simple correlation between rising acidity and rising emissions suffers from a statistical issue with respect to time scale as explained in a related post at this site:  [LINK]
18. Most of the warming occurred in the past 35 years. What is the significance of that in terms of proving the theory that the use of fossil fuels in the industrial economy has caused the world to be warmer than pre-industrial times? The human caused global warming hypothesis is tied to this pre-industrial time reference and to the consequences of the industrial economy. To shift over to arbitrary time spans depending on the data is circular reasoning and an appeal to the Texas Sharpshooter fallacy. Besides, if this 35-year period is the key to human caused climate change, one should consider the absence of empirical evidence for human cause in the last 40 years from 1979 to 2018 as shown in two related posts [LINK]  [LINK]  .

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