Climate Change

The earth has experienced roughly cyclical warming and cooling periods over at least the past 800,000 years, accompanied by roughly cyclical increases and decreases in atmospheric CO2. The positive temperature anomalies over this period have ranged from approximately +0.3 to +2.7°C, while the negative temperature anomalies have ranged from approximately -3 to -5°C. The lowest negative temperature anomaly in recent times was approximately -1.2°C in 1579, during the Little Ice Age. The current temperature anomaly is approximately 0.92°C, calculated in July 2021. Atmospheric CO2 concentrations have ranged from approximately 177 ppmv to the recent approximately 420 ppmv. Graphical presentations of this information can be viewed at the linked site by clicking on the icons at the upper left-hand corner of the graph. The darker lines on the 1000-year graphs represent the instrumental data period.

The shorter-term graphs do not show the Roman Warm Period, the Medieval Warm Period or the Little Ice Age as clearly as some other sources. While the graphs in the longer term reference above show a total temperature range of approximately 4°C over the past 800,000 years, the graph in the second reference shows a total temperature range of approximately 2°C over the past 4,500 years. This graph provides a clearer comparison of recent warm and cool periods including the modern warming period.

There was extensive discussion within the consensed climate science community approximately 10 years ago regarding the inconvenience of the Roman and Medieval warm periods, which could not be explained as being the result of increased atmospheric CO2 concentrations resulting from anthropogenic emissions, There was discussion of the advantages of “disappearing” these warm periods. There has recently been discussion in the consensed climate science community about the end of natural variation, suggesting that all recent changes in climate are the result of anthropogenic CO2 emissions.

However, there is no scientific basis for suggesting that the roughly cyclical pattern of global temperature change over the past 800,000 years has ceased, and that all temperature change over the past 70, or even 140, years has been the result of anthropogenic GHG emissions. There is no question that anthropogenic GHG emissions have occurred and that they have had some effect on global temperatures. However, there is also no scientific basis on which to assert that anthropogenic emissions are totally, or even primarily, responsible for increasing global temperatures. There is also no scientific basis upon which to allocate the anthropogenic influence on increased global temperatures among GHG emissions, land use changes and the Urban Heat Island effect on temperature measurements.

There is also little or no evidence that anthropogenic influence on climate has had any adverse impact on the frequency or intensity of weather events such as tropical cyclones, tornadoes, droughts, floods, heat and cold waves, wildfires, etc. However, there is evidence that increased atmospheric CO2 has had a dramatic positive impact on global greening, as well as a positive impact on the efficiency with which many common plant species use available water resources.

From: Climate Etc.

By: Judith Curry

Date: September 3, 2021

15 minutes

"In a recent invited talk at the American Chemical Society annual meeting, I attempted to explain the climate debate in 15 minutes.

This talk was given in a session on sustainability. Other invited speakers included James Green (NASA Chief Scientist), Marilyn Brown (Georgia Tech) . Our talks were followed by a panel discussion. This was an extremely interesting session, but was not recorded owing to an ACS glitch (you can read the abstracts at the link above)." ...

15 minutes

"A goal without a plan is just a wish." – Antoine de Saint-Exupéry

The Biden Administration has yet to release a plan to reach its stated CO2 emission reduction goals for 2030, 2035 and 2050. However, the Administration has taken several apparently disjointed actions which provide some hint of what the plan will involve. These actions present the potential of a very inconvenient and dangerous energy future for the US.

Intermittent renewable generation provided approximately 10.7% of US electricity generated for all uses in 2020. The Administration’s stated goal is to achieve 100% clean electricity by 2035, or within 13.3 years. The US currently has 1,117,475 MW of generating capacity, of which 66%, or 737,534 MW is fossil fueled and would need to be replaced by clean generators, primarily wind and solar. Assuming that the current shares of solar (~20%) and wind (~80%) continue into the future, total new intermittent renewable generating capacity of approximately 2,000,000 MW would be required to replace the entire fossil fuel generating fleet.

Wind turbines would constitute approximately 80% of the new generating capacity, requiring installation of 1,475,000 MW of wind turbine generating capacity. This would require production and installation of approximately 500,000 onshore 2 MW wind turbines, approximately 100,000 offshore 14 MW wind turbines, or some combination thereof. Solar PV collectors would constitute approximately 20% of the new generating capacity, requiring installation of approximately 590,000 MW of solar generating capacity, or approximately 1,475,000,000 solar collectors of 400W capacity. Note that these calculations are based on current electricity demand and consumption and make no allowances for the additional demand and consumption which would result from conversion to electric vehicles and the replacement of residential and commercial natural gas, propane and oil fueled appliances and equipment, most of which would likely occur after 2035.

The Administration has proclaimed that this transition would result in creation of millions of high paying union jobs, which implies that the production of the wind turbines and solar collectors would occur in the US. This would require preparation of numerous environmental impact statements by potential generation developers, review and approval of those impact statements by federal and state regulators and the issuance of building permits by federal and state authorities. This is currently a long, difficult and expensive process which could extend to, and likely beyond, 2025. This would also require the design, construction and commissioning of manufacturing facilities for the wind turbines and solar collectors, which could also extend to, and likely beyond, 2025.

Assuming such a schedule, achieving the Administration goal of 100% clean electricity by 2035 would require production and installation of approximately 100 wind turbines and approximately 400,000 solar collector panels per day. Also, each MW of generating capacity would require installation of 2-4 MW of grid-scale storage capacity to support the grid during multi-day periods of little or no generation due to weather conditions.

The scale of this effort might require the return of “Rosie the Riveter”. However, at this time, it all remains a wish.

From: Cliff Mass Weather Blog

Date: August 17, 2021

Climate Hype Hurts the Environment and Undermines Our Society

"Climate hype is profoundly damaging the environment and society; the evidence for this is compelling and discussed in this blog.

I have always been an environmentalist, worried about the protection of our natural environment. And I am concerned about global warming and its effects on humanity and the health of the planet.

Thus, I have become increasingly apprehensive about apocalyptic climate change hype, which is profoundly damaging the environment of our region and undermining the well-being of many.

Damage to the Northwest Environment from Climate Change Hype

There is substantial damage being done to the Northwest environment from the unfounded hype found in the media, some politicians, and several activist groups.  Consider a few examples:

Wildfires and Lack of Forest Management.  

Prominent politicians in our state and some media/activist groups have stated that climate change (a term used to mean human-caused global warming) is the predominant cause of the increase in regional fires and smoke.  

This is simply not true.  Regional forest experts (e.g., here and here) are emphatic that the key problems are unhealthy dry side forests, overgrown and explosive after decades of fire suppression, the invasion of flammable invasive grasses, and increasing fire ignitions by the rapidly growing population of our region.   Some knowledgeable local environmental leaders (e.g., Public Lands Commissioner Hilary Franz) have said the same thing." ...

Climate Hype Hurts the Environment and Undermines Our Society

Definition of confidence (Entry 1 of 2)

: a feeling or consciousness of one's powers or of reliance on one's circumstances

Definition of confidence (Entry 2 of 2)

: of, relating to, or adept at swindling by false promises

IPCC Guidance regarding confidence

A level of confidence is expressed using five qualifiers:
“very low,” “low,” “medium,” “high,” and “very high.” It
synthesizes the author teams’ judgments about the validity
of findings as determined through evaluation of evidence
and agreement. Figure 1 depicts summary statements
for evidence and agreement and their relationship to
confidence.

The IPCC AR6 Summary for Policymakers begins with the following Headline Statement:

It is unequivocal that human influence has warmed the atmosphere, ocean and land. Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.

This “unequivocal” statement is very carefully worded, as is the entire Summary for Policymakers. The specific human influences are not listed, nor are their relative contributions identified. The specific changes in the “atmosphere, ocean, cryosphere and biosphere” are also not listed, nor are they asserted to be “unequivocal”.

There is little doubt that increasing global population, clearing of forest land for cultivation, construction and expansion of cities, roads and highways and emissions of greenhouse gases cause warming of the local and regional climate and that the accumulation of this local and regional warming has warmed earth’s atmosphere. However, there is also little doubt that the natural variation in earth’s climate continues as well. It is not currently possible to separate the effects of human influence from the effects of natural variability.

The graph below prepared by Dr. Roy Spencer displays the entire history of satellite atmospheric temperature measurement. Even if one assumes that the increase in atmospheric temperature over the period is the result of human influence, the very rapid changes of atmospheric temperature above and below the trend line are clear and unequivocal evidence of the existence of natural variation, driven largely by ENSO events.

The graph below illustrates the evolution of IPCC “confidence” and “likelihood” assessments regarding CMIP5 climate model projections and contrasts them with the growing gap between the climate model projections and observations of both near-surface (adjusted) and satellite temperature.

The graph below by Dr. John Christy illustrates that the difference between model projections of temperature and observed temperature continues to grow in the CMIP6 model ensemble, while IPCC confidence in the likelihood of the model projections eventuating remains very high.

Dr. Christy concluded that the hypothesis embodied in the CMIP5 model ensemble had failed.

It appears clear that the hypothesis embodied in the CMIP6 models also fails, despite the IPCC’s apparent high confidence.

The IPCC guidance regarding confidence printed above speaks to evaluation of evidence and agreement. The observation trend shown in green above, while tainted by “adjustment”, is evidence of the warming global atmosphere. The model trend average shown in red above is representative of “agreement” by the IPCC parties, but is evidence that the models do not model the real atmosphere.

From: Real Climate Science

By: Tony Heller

Date: August 1, 2021

Extreme Fraud At NOAA

"NOAA’s Climate Extremes Index shows summer afternoon temperatures much above normal are affecting more and more of the US, with the past decade was highest on record.

They show an upwards trend beginning around fifty years ago.

U.S. Climate Extremes Index (CEI) | Extremes | National Centers for Environmental Information (NCEI)

"But their thermometer data shows the exact opposite, as does the National Climate Assessment. There are 1,218 stations in the United States Historical Climatology Network." ...

Extreme Fraud At NOAA

“A society, most of whose members spend a great portion of their time, not on the spot, not here and now and in the calculable future, but somewhere else, in the irrelevant worlds of sport and soap opera, of mythology and metaphysical fantasy, will find it hard to resist the encroachments of those who would manipulate and control it.”

“In their propaganda today’s dictators rely for the most part on repetition, suppression and rationalization – the repetition of catchwords which they wish to be accepted as true, the suppression of facts they wish to be ignored, the arousal and rationalization of passions which may be used in the interests of the Party or the State. As the art and science of manipulation come to be better understood, the dictators of the future will doubtless learn to combine these techniques with the non-stop distractions which, in the West, are now threatening to drown in a sea of irrelevance the rational propaganda essential to the maintenance of individual liberty and the survival of democratic institutions.”

Brave New World Revisited, Aldous Huxley

Aldous Huxley’s first paragraph above accurately describes a large portion of the population of the developed nations, distracted in their leisure by sports, television programs, computer games and fantasy roleplay.

The second paragraph above, while mentioning “dictators”, clearly describes the governing approach of many world ‘leaders”, both the elected heads of national governments and the would-be leaders of an aspirational global government and their bureaucratic hangers-on.

The subject of climate change provides excellent examples. The repetition of catchphrases such as “climate crisis”, “climate emergency” and “existential threat” is an attempt to create the impression in the populace that climate change is an urgent problem that must be dealt with quickly and aggressively. However, these are the terms of political science, not the hard science of climate change. The leaders using these terms know that the populace at large is too distracted to search beyond the hype and study the underlying science. The leaders are frequently the source of other distractions intended to distract the public from the issue.

The Climategate e-mails reveal a history of suppression of scientific results which differ from the accepted consensus narrative and dissenting opinions regarding the significance of CO2 and other GHG emissions on future climate. They also reveal a history of attempts to vilify and delegitimize scientists whose work differs from the consensus positions.

Government funding of studies intended to produce scary scenarios are an effort to arouse the public regarding climate change and to encourage them to demand a government response. The involvement of loud advocates for action, such as Grata Thunberg, and of numerous members of the industries which provide the public with irrelevant distractions contribute to public arousal and demands for action.

The global media have move well beyond reporting and have become advocates for action on climate change, supporting and promoting the consensus narrative. They are willing and uncritical participants in politicians’ efforts to move the public to demand action, while ignoring the potential impacts of government actions on the economy and the population’s lifestyles.

Scientists and others who question the consensus narrative are pounced upon by “factcheckers”, who are not really checking factual accuracy but rather consensus adherence. However, these same “factcheckers” completely ignore the history of failed predictions of imminent climate catastrophe made by climate alarmists.

From: Master Resource

By: Robert Bradley Jr.

Date: July 30, 2021

“Off Target”: Bad Economics of the Climate Crusade (mitigation not supported by mainstream analysis)

“Although advocacy of aggressive climate-change policies is often draped with the mantle of science, mainstream economists who follow the scientific literature have shown that the popular 1.5°C policy target will pose costs that far exceed the benefits, and that the emission reductions flowing from strict adherence to the 1.5°C target would be worse for the world than doing nothing at all.” (Murphy and McKitrick, below)

Adaptation, not mitigation, has long been the answer of climate economics for climate policy. In fact, at lower climate sensitivity estimates, carbon dioxide (CO2) emissions are thought to be a positive externality, in the jargon of economics, not a negative requiring government correction.

A new study by Robert P. Murphy and Ross McKitrick, Off Target: The Economics Literature Does Not Support the 1.5C Climate Ceiling, explains this to professional economists and the climate intelligentia alike. Released by the Fraser Institute (Canada), their short-and-sweet study uses the peer-reviewed literature to undermine a key assumption/goal of the United Nations Climate Conference of Parties (COP26), which is set for November in Glasgow, UK." ...

“Off Target”: Bad Economics of the Climate Crusade (mitigation not supported by mainstream analysis)

Strange decisions are being made by numerous global governments which have committed under the Paris Accords to reduce CO2 emissions in an effort to limit the increase in the global average temperature anomaly to 1.5°C.

China is building numerous new coal-fired electric generating stations and plans to build numerous additional coal-fired generating stations. China is also funding construction of new coal-fired generating stations in numerous other countries in Southeast Asia, the Middle East and Africa under its “Belt and Roads’ program. These new coal-fired generating stations would be expected to have useful lives of 40-60 years, suggesting either that they will continue to operate beyond the “Net Zero by 2050” timeframe or that their operation will be discontinued before the end of their useful lives, resulting in very large deadweight losses. Operation of these new coal-fired generating stations will obviously increase annual CO2 emissions, even if they are offset, in part, by emissions reductions achieved by other nations.

Russia is proceeding with construction of the Nordstream 2 natural gas pipeline, with the support and encouragement of the Western European nations which will be its customers, rather than replacing existing fossil energy consumption with renewable sources of energy such as wind and solar.

Several nations in western Europe are proceeding with plans to discontinue operation of their existing nuclear electric generating capacity, though many of those plants have not reached the end of their useful lives and the early closings will result in massive deadweight losses. This issue has the greatest potential impact in France and Germany, which have been heavily reliant on nuclear generation.

Numerous nations are encouraging a transition from gasoline and diesel vehicles to electric vehicles, though this transition would place additional pressure on electric generating systems already struggling to deal with the impacts of increasing intermittent wind and solar generation and the loss of baseload and load following generation capacity.

The actions announced by the US might perhaps be the most curious. The US Administration has committed to Net Zero electric generation by 2035. Numerous states are requiring the closure of nuclear generators, several of which have not reached the end of their useful lives. The Administration recognizes that the transition to solar and wind generation and to electric vehicles would require vast amounts of rare earth minerals but has announced that the mining of these minerals will not occur in the US, leaving the US dependent on other nations, primarily China, for these materials. The decision not to mine in the US also reduces the opportunities for the creation of “high paying union jobs” for miners displaced from high paying union jobs in the coal mining industry.

The US Administration also intends to incentivize installation of 500,000 electric vehicle charging stations and announced that these charging stations would be installed preferentially in disadvantaged and rural areas, even though these areas are not where electric vehicles are being purchased and operated, or where their owners would likely choose to go to charge them.

The US Administration has apparently decided to adopt the approach of starving markets of fossil fuels to force adoption of electric end use appliances and equipment, assuming that renewable electric supply will grow rapidly enough to meet the increased demand and consumption.

What could possibly go wrong with that scenario?

From: Watts Up With That

By: Eric Worrall

Date: July 28, 2021

Dr Willie Soon Predicts Global Cooling, Slams Politicised Science

"Dr. Willie Soon at his best, educating kids and adults at Camp Constitution about the politicisation of climate science, the exploitation of Greta Thunberg, failed climate predictions, the poor quality of mainstream science education, and the rise of the Technocracy, the growing risk from elitists who seek to subvert freedom by controlling ordinary people through manufactured fear." ...

Dr Willie Soon Predicts Global Cooling, Slams Politicised Science

Climate forecasts are essentially very long range (multi-decadal) weather forecasts. They are subject to the same types of uncertainties as long range weather forecasts, except that the magnitude of the uncertainties is far greater.

Climate forecasts rely almost exclusively on climate models which are hindcast to historical weather, then used to project future weather over multi-decadal periods. Climate models are hindered by the fact that numerous weather and climate phenomena are not well understood and thus not included in the models except by parameterization. Perhaps the most important of these phenomena is the impact of clouds on the climate which function as feedbacks in the models. Unfortunately, there is fundamental disagreement regarding whether cloud feedback is positive or negative, no less the magnitude of the feedback.

The temperature projections of the current CMIP5 ensemble of climate models have diverged from both satellite and near-surface temperature observations since the time at which hindcasting was used to “tune” the models to historical temperature observations. The CMIP5 models project global temperature anomalies two to three times greater than the observed anomalies, with the exception of a single Russian model. This suggests quite clearly that while the models are modeling something, they are not modeling the real global climate. Since the CMIP5 models have not accurately forecast global temperature anomalies over the period since “tuning”, it is clear that they have not been validated and verified and thus should not be assumed to have any predictive skill.

The CMIP6 models currently available for analysis appear to project even greater future temperature anomalies than the CMIP5 models, which have already falsified themselves. It is currently unclear why the CMIP6 models do not provide projections more consistent with current observations. If current trends continue, it appears that the CMIP6 models will be run with RCP8.5 or its successor to create even scarier potential future scenarios.

Variants of the CMIP5 models are being used in efforts to attribute some portion of the damages caused by weather events such as tropical cyclones, droughts, floods and wildfires to climate change. However, these models are unvalidated and unverified, so there is no reason to believe that the attributions they calculate have any credibility. Since the CMIP6 models appear to project even greater deviation from observations than the falsified CMIP5 models, there appears to be even less reason to assign any credibility to any attributions they calculate.

The forecasts of “climate crisis”, “climate emergency” and “existential threat” are based on scary scenarios produced by the CMIP5 climate models, run using RCP8.5. Since RCP8.5 has been demonstrated to be extremely unlikely, if not impossible, and the models have been progressively falsified, there appears to be no reason to assume that a “crisis” exists or impends. It appears that the CMIP6 models would support the “crisis” assertion, though they appear less credible than the falsified CMIP5 models.

The “climate crisis” appears to be a political construct designed to scare the citizenry into accepting energy poverty and increased government interference.

From: Climate Realism

By: Tim Benson

Date: July 26, 2021

Testimony on the Folly of Electrifying the U.S. Transportation System

Bryce Congressional Testimony Details Economic, Societal, National Security Hazards of Electrifying U.S. Transportation System

Testimony delivered before the House Select Committee on the Climate Crisis in June by Robert Bryce, a visiting fellow at the Foundation for Research on Equal Opportunity, raised a warning on the potential hazards of electrifying transportation and the regressive costs of continued federal subsidization of the sale of electric vehicles (EVs).

“Electrifying parts of our transportation system may result in incremental reductions in greenhouse gas emissions,” Bryce argued. “But a look at history, as well as an analysis of the supply-chain issues involved in manufacturing EVs, the resource intensity of batteries, and the increasingly fragile state of our electric grid – which is being destabilized by bad policy at the state and national levels – shows that a headlong drive to convert our transportation systems to run on ‘green’ electricity could cost taxpayers untold billions of dollars, increase greenhouse gas emissions, be bad for societal resilience, make the U.S. more dependent on commodity markets dominated by China, make us less able to respond to extreme weather events or attacks on our infrastructure, and impose regressive taxes on low and middle-income Americans in the form of higher electricity prices.” ...

Testimony on the Folly of Electrifying the U.S. Transportation System

Weather forecasting: the prediction of the weather through application of the principles of physics, supplemented by a variety of statistical and empirical techniques., Brittanica

There are fundamentally two types of weather forecasts. Short term forecasts (1-15 days ahead) are developed largely based on observation of existing weather patterns and projections of those patterns into the future while long term forecasts (seasonal or annual) are based on historical records and measured deviation of factors believed to affect the weather from historical norms. The availability of satellite imagery combined with wind speed and direction, temperature and humidity data and experience with development of weather in the region has allowed short term forecasts to be extended out to up to 15 days. However, the forecast accuracy declines as the forecast period is extended, because there are so may factors which can alter weather patterns over time.

One critical example of short term forecast weakness is the projection of the path and intensity of tropical depressions. The development of specific tropical depressions is not predictable. The existence of a tropical depression is identified from satellite imaging. The movement of the depression is then tracked and its intensity measured.

There is no certainty that any specific tropical depression will develop into a tropical storm or ultimately into a tropical cyclone (hurricane or typhoon) of some intensity. Satellite monitoring of the depression is used to determine whether it has developed into a tropical storm, at which point aircraft monitoring of storm wind speed and barometric pressure documents further development and storm path and speed. Multiple computer models are then used to project future path and intensity.

Similarly, weather observations can establish that conditions are suitable for the development of severe thunderstorms and tornadoes, but the development of a specific tornado or cluster of tornadoes is not predictable. Tornado strength and direction are also not predictable, though they are closely monitored once development has occurred.

Examples of long term weather forecasts include the seasonal tropical cyclone forecasts developed annually by the National Hurricane Center. These forecasts are developed based on historical experience combined with analysis of deviation of factors such as sea surface temperature deviations from historical norms. They provide estimated ranges of number of named storms, number of hurricanes by intensity category and number of projected landfalls. However, the National Hurricane Center was not able to predict the 12 year “hurricane drought” during which no category 3 or higher hurricanes made landfall in the US, nor the recent 3 year “hurricane drought” in which no hurricanes formed in the Gulf of Mexico.

Other examples of long term weather forecasts include seasonal projections of regional temperature deviations from climatological norms, drought location and duration, winter snow cover. These forecasts are subject to frequent revisions as unpredictable events and conditions affect the anticipated weather patterns.

The accuracy of both short term and long term forecasts will continue to improve as  instrumental data and satellite observations accumulate and our understanding of our complex and chaotic atmosphere improves.

From: edmhdotme

Date: June 26, 2021

Global Man-made CO2 Emissions 1965 – 2020: BP Data

"Introduction

Every summer BP publish their statistical review of world energy.

https://www.bp.com/en/global/corporate/energy-economics/statistical-review-of-world-energy.html

One element of their comprehensive set of spreadsheets is a table of CO2 emissions country by country since 1965.  For the purposes of this post, the CO2 emissions data provided by BP here is assumed to be valid.

The 2020 dataset takes begins to account for the effect of the COVID epidemic, its impact on Global economic activity and the outcome for Man-made CO2 emissions in that year.

"The progress of the proportions of CO2 emissions since 1965 is shown above, with the  Developed world now being responsible for about 35% of Man-made CO2 emissions as opposed to as much as 86% back in 1965.

The BP country by country data is aggregated here into seven Nation groups according to their nominal state of development and attitudes towards controlling CO2 emissions, as follows:" ...

Global Man-made CO2 Emissions 1965 – 2020: BP Data

“There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don't know. But there are also unknown unknowns. There are things we don't know we don't know.”, 
Donald Rumsfeld

Known Knowns (Things we know we know.)

• Earth has climates, which are aggregated to a global climate.
• Earth’s climates have changed in the past.
• Earth’s climates are changing now.
• Global aggregate climate is changing now.
• Earth has experienced glacial periods.
• Earth has experienced interglacial periods.
• Earth has experienced warmer and cooler periods during interglacials.
• Earth’s average near-surface temperature is rising.
• Earth’s sea surface temperature is rising.
• Earth’s sea level is rising.
• Human actions are adding CO2 and other chemicals to the atmosphere.
• CO2 and Methane absorb and reradiate infrared energy in the atmosphere.
• Water vapor is the primary absorber and re-radiator of infrared energy in the atmosphere.
• Human actions are changing earth’s albedo.
• Human cities create urban heat islands.
• The globe is greening, largely as the result of increased atmospheric CO2.
• Increased atmospheric CO2 makes plants grow faster and use water more efficiently.
• Earth’s seas are absorbing more CO2 and becoming slightly less basic.
• Earth’s oceans experience warm and cool phases. (AMO, PDO)
• ENSO produces localized warming and cooling of the Pacific Ocean.
• We have no comprehensive, validated and verified model of earth’s climate.
• We have no validated and verified attribution model.

Known Unknowns (Things we know we don’t know.)

• The factors which trigger glacial periods.
• The factors which trigger interglacial periods.
• The duration of interglacial periods.
• The relative effects of those factors.
• The factors which cause climate to change within glacial and interglacial periods.
• The factors which determine when those climate changes occur.
• The factors which determine the magnitude of those climate changes.
• The factors which determine the duration of those climate changes.
• The factors which determine whether those climate changes will be warmer or cooler.
• The global average near-surface temperature.
• The global average sea surface temperature.
• The global average ocean temperature.
• The global average near-surface temperature anomaly.
• The global average sea surface temperature anomaly.
• The global average rate of sea level rise.
• The impacts of human activity on future global average near-surface temperature.
• The impacts of human activity on future global average sea surface temperature.
• The impacts of climate change on tropical cyclones.
• The impacts of climate change on tornadoes.
• The impacts of climate change on droughts.
• The impacts of climate change on floods.
• The sensitivity of the atmosphere to a doubling of atmospheric CO2
• The magnitude of cloud feedback and whether it is positive or negative.
• The Social Cost of Carbon (Dioxide).
• The future Resource Consumption Pathway.

Unknown Unknowns (Things we don’t know we don’t know.)

• We just do not know.

In summary, we know generally what has happened in the past and what is happening now. We do not clearly understand how and why what happened in the past happened. We do not clearly understand how and why what is happening now is happening. We do not have the validated and verified tools to comprehensively model the current atmosphere, no less to predict with confidence what will happen in the future. We have produced advanced satellite measurement tools, but have yet to resolve the differences between their measurements and our historical direct measurements.

Regardless, we continue to report with two decimal place precision numbers we do not know to one decimal place accuracy, to make future climate projections based on incomplete models and uncertain feedbacks, and to attribute weather change to climate change with unvalidated and unverified models.