donsutherland1

Yes, but that’s well before the Holocene. Nevertheless, what one is witnessing today is highly unusual.

The rate of warming has been unprecedented for the Holocene. For a graph that goes well beyond the Holocene for even greater perspective: https://www.sciencemag.org/news/2019/05/500-million-year-survey-earths-climate-reveals-dire-warning-humanity Sea levels are rising as ice caps and glaciers are melting. Finally, the scientists have already demonstrated that anthropogenic factors are responsible for most of the recent warming.

Mann’s paper laid out the basis for the “hockey stick.” The basic findings and the temperature reconstruction (aka the hockey stick) were validated. Thus the reconstruction is not a “fraud.”

Scientific understanding advances through research. That research is published in peer-reviewed journals. The topic at hand concerns anthropogenic climate change. No other alternative explanation can explain the recent dramatic warming that has occurred since 1950. Mann’s research has contributed to a solid scientific understanding. If anthropogenic climate change is “fraud,” one should have credible scientific research to expose it. Such credible research does not exist, because the scientific basis is sound. Earlier, I provided a link to subsequent research that validated Mann’s paper. No one has provided a link to any paper that overturns it. That’s where things stand. Finally, the reference to policy was an illustration to show that the world is moving to applying the scientific understanding. The scientific question, with the exception of some nuances, residual uncertainties, and details about feedbacks is largely settled on the cause of the ongoing observed warming.

Hopefully, others who read these pages will realize that, notwithstanding erroneous Social Media claims, Mann’s “Hockey Stick” has been validated by subsequent research. The good news is that the world has largely moved on from the past debate over whether climate change is occurring (it is) and whether it is principally driven by anthropogenic activities (it is). Those who reject the now near unequivocal consensus among climate scientists have had decades to provide a plausible and empirically robust alternative to AGW. They have not. Among the Millennials and Generation Z, the fundamental basis of climate change is widely understood. The urgency of addressing that great global challenge is also well understood. It’s those generations that will, as their political influence and participation grows, put an end to efforts to thwart the policy making necessary to address climate change.

His paper did not reach conclusions “regardless to which set of numbers was used.” As a result, the paper has largely withstood the test of time. Today, at least in the scientific field, it is considered among the breakthrough works that have informed the evolution of understanding of climate change. If you can point me to peer-reviewed research that finds his basic conclusion was wrong, please share it. The studies that followed largely upheld the paper with some revisions for the 1400-1500 period. The most important part concluding that the warming during the late 20th century (which has now been exceeded in the early 21st century) was greater than anything that had occurred during the prior 600 years was reaffirmed in the follow-up research. Today, there is no serious debate that the current global temperatures are unprecedented during the current 1,000 years. Within a few decades or less, they will likely be the warmest of the entire Holocene Interglacial Period. Moreover, the warming is more abrupt and rapid than anything that took place in the Holocene. Taking potshots at modeling to evade the largely sound conclusions of Dr. Mann’s paper is the “strawman.” Moreover, the modeling from the 1970s and 1980s, even as it was fairly rudimentary at that time, has proved quite accurate.

Tomorrow and Friday will feature much warmer than normal conditions. The temperature will generally reach the middle and upper 80s across the region. A few hot spots could reach 90°. A deep trough will move from Canada toward the Great Lakes Region and into the Northern Plains starting this weekend. This trough will likely provide a period of somewhat cooler weather. Most of the colder air will stay west of the Appalachians. That trough may persist until near or just after mid-month. Nevertheless, the first half of September will likely wind up somewhat warmer than normal. The ENSO Region 1+2 anomaly was -0.6°C and the Region 3.4 anomaly was -0.7°C for the week centered around August 26. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.02°C and the ENSO Region 3.4 anomaly has averaged -0.63°C. Neutral-cool conditions will likely evolve into La Niña conditions during the fall. The SOI was +20.15. Today, the preliminary Arctic Oscillation (AO) figure was +0.502. On September 1, the MJO was in Phase 3 at an amplitude of 1.421 (RMM). The August 31-adjusted amplitude was 1.655. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Finally, on September 1, Arctic sea ice extent was 3.895 million square kilometers (JAXA). Based on the August 31 figure, minimum Arctic sea ice extent will most likely finish somewhere from 3.645 million to 3.695 million square kilometers in September. The highest 25% bound is 3.742 million square kilometers. The lowest 25% bound is 3.581 million square kilometers. 2020 is the second consecutive year with a minimum extent figure below 4.000 million square kilometers and the third such year on record.

Mann created his landmark temperature chart from multiple lines of proxy data and the instrument record.

Much of Mann’s construction, including the “blade” illustrating the anomalous late 20th century warming were reaffirmed in subsequent research. https://ral.ucar.edu/projects/rc4a/millennium/refs/Wahl_ClimChange2007.pdf

Article on Phoenix’s historic summer by The Washington Post’s Capital Weather Gang: https://www.washingtonpost.com/weather/2020/09/01/phoenix-hottest-summer

He is a scientist: http://www.met.psu.edu/people/mem45 His work has also been cited more than 38,000 times.

Here is the extended information that includes the 30-year periods ending in 1930 and 1940 for Phoenix. Average Summer Temperatures (30-Year Moving Average):

I have confidence in the large and growing body of peer-reviewed research on the matter. Further, there is no alternative explanation that even begins to account for the observed warming that has occurred since 1950. Models that rely solely on natural forcings cannot reliably reproduce the warming. Those that include anthropogenic greenhouse gases do very well.

Initially, one could make a compelling argument that Phoenix’s warming was being driven by growing urbanization. But that has changed. During the 1990-2020 period, the 30-year moving average for summer temperatures rose 2.7° at Phoenix but 1.4° at Tombstone (current population 1,330). However, if one excludes the 1990s, the increases were 1.5° and 1.0° respectively. Since 2010, Tombstone actually saw greater warming than Phoenix, even as its population fell slightly from 1,382. In addition, as with Phoenix, a disproportionate share of Tombstone’s 10 warmest summers have occurred since 2000. In fact, 9 of Tombstone’s 10 warmest summers have occurred since 2010. In sum, the recent data is consistent with what the overwhelming body of scientific research shows overall: Most of the recent warming is related to anthropogenic climate change, not location-specific factors such as the Urban Heat Island (UHI) effect. Not surprisingly, IPCC is considering raising the level of confidence about the role of anthropogenic factors leading to most of the recent warming to 99%-100% for the Sixth Assessment Report that will be published next year.

Urbanization was cited as one of three factors by the National Weather Service. Climate change was another. Moreover, the idea that urbanization is responsible for the outcome was addressed by NWS Phoenix which stated, "The record summer heat wasn't just in Phoenix, or solely due to Urbanization. A large chunk of the SW saw exceptional heat and all-time records. Some other locations w/ all-time summer records: Lost Dutchman SP, Carefree, Tombstone, Tucson, & Nogales."

Morning thoughts... At 8:20, a large area of light rain with some embedded heavier showers was moving eastward across southern and central New York State and Connecticut. The rain was north of New York City. Another area of showers was located in eastern Pennsylvania. Today will be mostly cloudy with some showers. Thundershowers are possible this evening and tonight as a warm front moves northward. Temperatures will will reach the upper 70s and lower 80s across the region. Likely high temperatures around the region include: New York City (Central Park): 80° Newark: 83° Philadelphia: 85° Tomorrow and Friday will be noticeably warmer days. Afterward, a deep trough in Canada will move toward the Great Lakes Region and provide a period of somewhat cooler weather. That trough may persist until near mid-September.

Tomorrow will be partly to mostly cloudy with possible showers and perhaps a thundershower. Total rainfall amounts will generally be 0.25" or less. Afterward, temperatures will likely return to above normal levels for several days. However, a deep trough will move from Canada toward the Great Lakes Region and into the Northern Plains starting this weekend. This trough will likely provide a period of somewhat cooler weather. Most of the colder air will stay west of the Appalachians. That trough may persist until near or just after mid-month. Nevertheless, the first half of September will likely wind up somewhat warmer than normal and September, as a whole, will likely finish warmer than normal (generally 1°-3° above normal). The ENSO Region 1+2 anomaly was -0.6°C and the Region 3.4 anomaly was -0.7°C for the week centered around August 26. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.02°C and the ENSO Region 3.4 anomaly has averaged -0.63°C. Neutral-cool conditions will likely evolve into La Niña conditions during the fall. The SOI was +18.44. Today, the preliminary Arctic Oscillation (AO) figure was +0.464. On August 31, the MJO was in Phase 3 at an amplitude of 1.654 (RMM). The August 30-adjusted amplitude was 1.626. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Finally, on August 31, Arctic sea ice extent was 3.943 million square kilometers (JAXA). Based on the August 31 figure, minimum Arctic sea ice extent will most likely finish somewhere from 3.645 million to 3.695 million square kilometers in September. The highest 25% bound is 3.742 million square kilometers. The lowest 25% bound is 3.581 million square kilometers. 2020 is the second consecutive year with a minimum extent figure below 4.000 million square kilometers and the third such year on record.

Scientists are able to tell that anthropogenic activities have led to most of the increase in atmospheric concentration of CO2. The carbon atoms in fossil fuels are “light.” The increase in atmospheric CO2 has been occurring while the ratio of “light” - to - “heavy” carbon has been increasing, as well. Thus scientists are confident about the reason the atmospheric concentration of CO2 is rising.

Another tweet from the Phoenix office of the National Weather Service: https://twitter.com/NWSPhoenix/status/1300795549499756544?s=20

When the IOD is positive, the MJO is often in more favorable phases. However, long-term changes in sea surface temperatures are promoting an increased tendency for the MJO to reside in the Maritime Continent. Here's a paper @bluewave posted on this topic: https://www.nature.com/articles/s41586-019-1764-4

Morning thoughts... Overnight, showers brought 0.12" rain to New York City and Newark. Those showers are now departing from the region. The remainder of today will be partly to mostly cloudy. There could still be another shower. Temperatures will be in the 70s across much of the area except near or just above 80° in southern New Jersey southward. Likely high temperatures around the region include: New York City (Central Park): 76° Newark: 79° Philadelphia: 81° Temperatures will likely return to above normal levels near or just after mid-week. Afterward, a deep trough in Canada will move toward the Great Lakes Region and provide a period of somewhat cooler weather. That trough may persist until near mid-September. Phoenix, which just experienced its hottest summer, by far, could see a new period of excessive heat develop late this week.

From the NWS Phoenix forecast office:

Anthropogenic greenhouse gases are the dominant variable driving the changes.

The IOD state at this time of year doesn’t seem to have much influence. During the winter, and IOD- has often seen an increased tendency for the MJO to reside in the Maritime Continent phases (Phases 4 and 5).

Because the empirical evidence is strong. It assumes basic understanding that statistics measure things. Statistics are not abstractions unto themselves. The changes taking place are leading to warmer, drier conditions in general. The incidence of extreme heat, including this August’s record-breaking heat in parts of California and Arizona have increased the frequency of conditions that are conducive for wildfires.