donsutherland1

Also, there on September 4, Israel and Cyprus set national record high temperatures for September. Jerusalem reached 109.

Morning thoughts... Today will be mostly sunny and pleasant. Temperatures will likely reach the lower 80s across much of the region. Likely high temperatures around the region include: New York City (Central Park): 81° Newark: 83° Philadelphia: 83° Somewhat warmer than normal conditions will likely prevail through much of next week. The historic September heat will continue in the Southwest. Death Valley, which reached 125° yesterday, could approach or even exceed that mark today.

Denver has had one case where there was measurable snow the day after the temperature hit 90 degrees. On September 12, 1993, the temperature reached 92 degrees. On September 13, 5.4” snow fell.

Tomorrow will see sunshine and readings generally in the lower 80s across the region. Overall, the first half of September will likely wind up somewhat warmer than normal. The probability of the arrival of an autumn-like air mass after mid-month has increased. The historic September heat wave of 2020 scorched the Southwest for another day. Select high temperatures included: Casper: 98° (old record: 95°, 1978) ***Tied September Record*** Cheyenne: 94° (old record: 92°, 1998 and 2019) Death Valley, CA: 125° (old record: 120°, 1955) ***New September Record*** Denver: 101° (old record: 98°, 2019) ***New September Record*** El Centro, CA: 121° (old record: 114°, 1934 and 1945) ***New September Record*** Flagstaff: 90° (old record: 89°, 1945) Kingman, AZ: 109° (old record: 104°, 1908) ***New September Record*** Lake Havasu City, AZ: 117° (old record: 115°, 2011) Las Vegas: 112° (old record: 109°, 1947, 1955 and 1977) Needles, CA: 119° (old record: 114°, 1891 and 1923) Palm Springs, CA: 122° (old record: 116°, 1955) ***New September Record*** Phoenix: 115° (old record: 113°, 1945) Pueblo, CO: 100° Reno: 100° (old record: 99°, 2017) Tucson: 108° (old record: 107°, 1945) Yuma, AZ: 120° (old record: 115°, 1945) Death Valley reached 125°. That broke the September record of 123°, which was set on September 2, 1996. El Centro, CA reached 121°. That surpassed both the existing August and September records. The previous latest 120° or above reading on record there occurred on July 28, 1995 when the temperature reached 121°. Since 1925, there have been just 10 days on which the temperature reached 120° or above at El Centro. Seven occurred since 2000 and six occurred since 2010. Phoenix reached at least 115° for the 14th time this year. The previous annual record for 115° or warmer was 7 days in 1974. Separately, Miami reached 93°, which tied the daily record set in 1996 and tied in 2017 and 2019. Today was Miami's 49th day where the temperature reached 93° or above. The previous record was 44 days, which was set just last year. 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 +8.56. Today, the preliminary Arctic Oscillation (AO) figure was -0.045. On September 4, the MJO was in Phase 3 at an amplitude of 1.015 (RMM). The September 3-adjusted amplitude was 1.018. 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 4, Arctic sea ice extent data was not available. On September 2, Arctic sea ice extent was 3.861 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.

Two papers: https://iopscience.iop.org/article/10.1088/1748-9326/10/1/014005 https://www.nature.com/articles/s41467-018-05256-8.epdf

Morning thoughts... Today will be mostly sunny and cooler than yesterday. Temperatures will likely reach the upper 70s and lower 80s across the region. Likely high temperatures around the region include: New York City (Central Park): 79° Newark: 81° Philadelphia: 81° A deep trough will continue to move into the Northern Plains in coming days. However, the cold will likely remain west of the Appalachians through at least much of next week. Extreme heat will again scorch the Southwest. Numerous cities will approach or set daily record temperatures with some September records approached or broken. Death Valley could see the temperature top out near or just above its monthly record of 123°.

The latest Needles hit 120 was September 1, 1950.

There is some research indicating that Arctic Amplification also has an impact on the summer weather pattern in addition to that of the fall. In general, one line of thought is that it is leading to greater persistence of events due to a wavier and slowing jet stream.

Actually, the UAH has had documented issues. RSS, RATPAC, etc., are better tools. That UAH is an outlier highlights its issues. One paper: https://journals.ametsoc.org/jtech/article/34/1/225/342433

It’s tough to know. But some of the studies suggest that New York City will have a climate similar to Virginia Beach by 2050.

Cooler air will return starting tomorrow as a deep trough moves from Canada toward the Great Lakes Region and into the Northern Plains. The coldest air associated with this trough will likely remain mainly 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. Another bout of extreme heat commenced in the Southwest in spectacular fashion in which two monthly records were toppled. Select high temperatures included: Blythe, CA: 115° (tied record set in 1948) Death Valley: 122° (old record: 121°, 2007) Denver: 91° Flagstaff: 90° (tied record set in 1945) Kingman, AZ: 107° (old record: 104°, 2019) Lake Havasu City: 115° (old record: 114°, 1993, 1995 and 2007) Las Vegas: 109° Needles, CA: 117° (old record: 116°, 2019) Palm Springs, CA: 116° (tied record set in 1955) Phoenix: 114° (old record: 112°, 1945 and 2019) Reno: 102° (old record: 100°, 1988 and 2017) ***New September Record*** Tucson: 110° (old record: 106°, 1945 and 2011) ***New September Record*** Yuma, AZ: 114° Until today, Tucson's latest season 110° or above temperature occurred on August 22, 1930 when the temperature also topped out at 110°. September 2020 became the 4th consecutive September during which the temperature reached 120° or above. Prior to the current stretch, the record was two consecutive years. The temperature was also the hottest September temperature since September 2, 2017 when the mercury also reached 122°. Only September 2, 1996 with a high temperature of 123° was hotter in September. That record could be challenged tomorrow and Sunday. 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 +6.78. Today, the preliminary Arctic Oscillation (AO) figure was -0.198. On September 3, the MJO was in Phase 3 at an amplitude of 1.018 (RMM). The September 2-adjusted amplitude was 1.063. 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 3, Arctic sea ice extent data was not available. On September 2, Arctic sea ice extent was 3.861 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.

Some numbers for Denver: 27 cases where measurable snow fell a day after the temperature hit 80 degrees or above. Highest temperature preceding a measurable snow event: 92 degrees, September 12, 1993 (5.4" snow fell on September 13) Most recent case: October 9, 2019: 83 degrees (1.0" fell on October 10)

Morning thoughts... Today will be mainly sunny and quite warm. Temperatures will likely reach the middle and upper 80s across the region. Likely high temperatures around the region include: New York City (Central Park): 85° Newark: 87° Philadelphia: 86° Cooler air will return for the weekend as a deep trough will move from Canada toward the Great Lakes Region and into the Northern Plains. Another round of dangerous heat will develop in the Southwest today. Parts of Arizona, California, Colorado, and Nevada could see several days of near record to record high temperatures. Following the heat, parts of Colorado and Wyoming, including Denver, could see their first snowfall of the season next week.

Back last year, Eric Blake of the National Hurricane Center tweeted about Miami’s record 42nd day with a high temperature of 93 degrees or above. 2019 went on to finish with 44. Through September 4, 2020 has had 48 such days. 2019 also went on to record an annual mean temperature of 79.1 degrees, which tied 2017 for the second warmest year on record 2015, with an annual mean temperature of 79.2 degrees, is Miami’s warmest year on record.

Temperatures generally ranged from the middle to upper 80s in the Middle Atlantic region. Highs included: Allentown: 83° Baltimore: 89° New York City-JFK: 86° New York City-LGA: 89° New York City-NYC: 85° Newark: 89° Philadelphia: 87° Washington, DC: 91° 90° Days for Select Cities (through September 3): Albany: 13 (2019: 12 days) Allentown: 24 (2019: 24 days) Baltimore: 46 (2019: 59 days) Boston: 14 (2019: 15 days) Burlington: 20 (2019: 8 days) Harrisburg: 34 (2019: 33 days) Hartford: 39 (2019: 27 days) Islip: 8 (2019: 8 days) New York City-JFK: 12 (2019: 7 days) New York City-LGA: 34 (2019: 26 days) New York City-NYC: 20 (2019: 15 days) Newark: 31 (2019: 28 days) Philadelphia: 36 (2019: 35 days) Scranton: 25 (2019: 12 days) Washington, DC: 45 (2019: 62 days) Tomorrow will again see the temperature reach the middle and upper 80s across the region. A few hot spots could reach 90°. Cooler air will return for the weekend as a deep trough will move from Canada toward the Great Lakes Region and into the Northern Plains. The coldest air associated with this trough will likely remain mainly 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 +12.60. Today, the preliminary Arctic Oscillation (AO) figure was unavailable. On September 2, the MJO was in Phase 3 at an amplitude of 1.063 (RMM). The September 1-adjusted amplitude was 1.422. 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 2, Arctic sea ice extent was 3.861 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.

MBH98 has not been disproven. Excerpts from a review of the MBH reconstruction: The results presented here show no evidence for removing the MBH Northern Hemisphere temperature reconstruction from the list of important climate reconstructions of the past six centuries, on the basis of alleged “flaws” in its use of proxy data or underlying methodology. Indeed, our analyses act as an overall indication of the robustness of the MBH reconstruction to a variety of issues raised concerning its methods of assimilating proxy data, and also to two significant simplifications of the MBH method that we have introduced. The shape of a single-bladed “hockey stick”-like evolution of Northern Hemisphere temperature over the last 600 years is strongly confirmed within the MBH reconstruction framework (general algorithm and proxy data). Questions of potential loss of downward amplitude in the MBH method remain, but the evidence developed here from the perspective of the proxy data themselves suggests such losses may be smaller than those shown in other recent work. http://www.rap.ucar.edu/projects/rc4a/millennium/refs/Wahl_ClimChange2007.pdf

Morning thoughts... Today will feature sunshine and much warmer conditions. Temperatures will likely reach the middle and upper 80s across the region. A few hot spots could reach 90°. Likely high temperatures around the region include: New York City (Central Park): 85° Newark: 88° Philadelphia: 88° Cooler air will return for the weekend as a deep trough will move from Canada toward the Great Lakes Region and into the Northern Plains. Finally, starting tomorrow, another round of dangerous heat will develop in the Southwest. Parts of Arizona, California, and Nevada could see several days of near record to record high temperatures.

A new paper on climate change and California’s wildfire risks: https://iopscience.iop.org/article/10.1088/1748-9326/ab83a7

The issue isn’t whether humans can “overpower” such past events, but whether humans can have a significant impact on the climate. The science is unambiguous. Human greenhouse gas emissions are now the main driver of the rapid observed warming. Moreover, humans are releasing CO2 at a rate 10 times faster than has occurred at any other time over the past 66 million years. https://www.sciencedaily.com/releases/2016/03/160321123656.htm

Those are over millions of years not hundreds of years.

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.