No, Covid is not a Heart Disease
Posted on September 29, 2020 Leave a Comment
Update September 29, 2020 No, Covid19 is not Heart Disease
Government officials and journalists stoked fears of heart disease following SARS-CV2 infection, even when asymptomatic or with only mild discomfort. Two flawed studies were exploited and are now challenged by experts objecting to the exaggerations favoring restrictive policies.
Sara Talpos writes at Undark Experts Raise Questions Over ‘Scary’ Covid Heart Studies. Excerpts in italics with my bolds.
Some scientists say recent research on heart inflammation, even in asymptomatic Covid-19 patients, is being overblown
But over the course of roughly a dozen Undark interviews with physicians and researchers specializing in cardiac radiology, cardiac pathology, and sports cardiology, several expressed concerns over the limitations of the German research, and with a more recent heart imaging study published by a team at The Ohio State University. Some also shared deep misgivings about how the findings of these small studies are being interpreted, reported, and used in the wider world. September’s media coverage has been more circumspect, but these preliminary findings are already being used to guide treatment of virus-positive athletes.
While the experts agreed that Covid-19 can harm the heart, the severity and frequency of the outcomes, as well as how to test for myocarditis, is under fierce debate.
The Big Ten and Pac-12 have since reversed course, with plans to resume their seasons this fall, but the implications of this new research go beyond football. Many experts worry about broader, graver consequences, including the overuse of the pricey heart scans — known as cardiac MRI — and unduly frightening Americans, both of which, they say, could jeopardize public trust in science.
A summary published by The American College of Cardiology made similar points, concluding: “While this study adds to emerging data, it does not imply that CMR should be performed in all Covid-19 positive patients to screen for myocardial inflammation.” A few days later, an open letter appeared online. It had been initiated by Murthy and was cosigned by roughly 50 medical professionals. Addressed to 18 medical societies, the letter asked them to discourage the use of cardiac MRIs on asymptomatic people who test positive for Covid-19.
Michael Ackerman, a genetic cardiologist at the Mayo Clinic who has no professional ties to any of the college sports conferences, took issue with the “spookiness” that was being assigned to myocarditis. “If this is the reason why a conference is shutting down a sport,” he said, “I call nonsense on that.”
Continuing Pattern of Media Fear-Mongering over Covid
Previous Post: Alex Berenson explains in a twitter thread (here). Text in italics with my bolds
1/ This panic is likely to prove even more embarrassing than previous panics. Here’s why: the media is both confused and conflating several different data points in an effort to stir hysteria. (Stop me if you’ve heard this before.)
What do I mean?
2/ So: you’ve heard positive tests are up in several states. True. The media refers to these as “cases,” as if positive tests have clinical significance by themselves. They do not. The vast majority of people with positive tests do not become ill enough to need hospitalization…
3/ Much less intensive care or ventilator support. For people under 50, this is true in the extreme. But the daily age distribution of positive tests is rarely if ever supported…
4/ Second: you’ve heard overall hospitalizations are up in some states. This is also true. THIS IS A FEATURE, NOT A BUG. Overall hospitalizations are rising because people are returning to hospitals for elective (and in some cases very necessary) surgeries that were postponed…
5/ Now, in some of these states COVID-related hospitalizations have also risen (though they make up a tiny fraction of overall hospitalizations). Scary, right?
No. When people go to the hospital for elective surgeries they are now routinely tested for COVID...
6/ Whether or not they are symptomatic. Hospitals have financial and legal as well as medical incentives to do this. IF THEY ARE POSITIVE, hospitals will report them as COVID patients (since, technically, they are), EVEN IF THEY HAVE NO COVID SYMPTOMS.
7/ This fact accounts for the bizarre disconnect between the fact the number of people going to emergency rooms with influenza-like or COVID-like symptoms is NOT rising (and remains in the low single digits) even in states reporting more hospitalizations…
8/ As well as the fact that fewer hospitalized cases are now progressing to ventilators (I can’t swear to this in every state, but it appears to be a trend)…
9/ And the fact that deaths no longer seem to have any relationship to case counts in many states (true even accounting for the fact that deaths lag).
The question you should be asking yourself: why aren’t Europe and Asia seeing post-lockdown spikes if this trend is real?
10/ And don’t say masks. Masks are not routine in Europe. So either COVID is somehow different post-lockdown in Europe (and different in different states, too)… or this is just one last gasp of panic porn.
And if you want confirmation from epidemiologists, here Facts about Covid-19 from Swiss Policy Research.
Fully referenced facts about Covid-19, provided by experts in the field, to help our readers make a realistic risk assessment. (Regular updates below)
“The only means to fight the plague is honesty.” (Albert Camus, 1947)
Overview
1.According to the latest immunological and serological studies, the overall lethality of Covid-19 (IFR) is about 0.1% and thus in the range of a strong seasonal influenza (flu).
2. Even in global “hotspots”, the risk of death for the general population of school and working age is typically in the range of a daily car ride to work. The risk was initially overestimated because many people with only mild or no symptoms were not taken into account.
3. Up to 80% of all test-positive persons remain symptom-free. Even among 70-79 year olds, about 60% remain symptom-free. Over 95% of all persons develop at most moderate symptoms.
4. Up to 60% of all persons may already have a certain cellular background immunity to Covid19 due to contact with previous coronaviruses (i.e. common cold viruses).
5. The median or average age of the deceased in most countries (including Italy) is over 80 years and only about 4% of the deceased had no serious preconditions. The age and risk profile of deaths thus essentially corresponds to normal mortality.
6. In many countries, up to two thirds of all extra deaths occurred in nursing homes, which do not benefit from a general lockdown. Moreover, in many cases it is not clear whether these people really died from Covid19 or from weeks of extreme stress and isolation.
7. Up to 30% of all additional deaths may have been caused not by Covid19, but by the effects of the lockdown, panic and fear. For example, the treatment of heart attacks and strokes decreased by up to 60% because many patients no longer dared to go to hospital.
8. Even in so-called “Covid19 deaths” it is often not clear whether they died from or with coronavirus (i.e. from underlying diseases) or if they were counted as “presumed cases” and not tested at all. However, official figures usually do not reflect this distinction.
9. Many media reports of young and healthy people dying from Covid19 turned out to be false: many of these young people either did not die from Covid19, they had already been seriously ill (e.g. from undiagnosed leukaemia), or they were in fact 109 instead of 9 years old. The claimed increase in Kawasaki disease in children also turned out to be false.
10. The normal overall mortality per day is about 8000 people in the US, about 2600 in Germany and about 1800 in Italy. Influenza mortality per season is up to 80,000 in the US and up to 25,000 in Germany and Italy. In several countries Covid19 deaths remained below strong flu seasons.
11. Regional increases in mortality can occur if there is a collapse in the care of the elderly and sick as a result of infection or panic, or if there are additional risk factors such as severe air pollution. Special regulations for dealing with the deceased sometimes led to additional bottlenecks in funeral or cremation services.
12. In countries such as Italy and Spain, and to some extent the UK and the US, hospital overloads due to strong flu waves are not unusual. In addition, up to 15% of doctors and health workers are now being put into quarantine, even if they develop no symptoms.
13. The often shown exponential curves of “corona cases” are misleading, as the number of tests also increased exponentially. In most countries, the ratio of positive tests to tests overall (i.e. the positive rate) remained constant at 5% to 25% or increased only slightly. In many countries, the peak of the spread was already reached well before the lockdown.
14. Countries without curfews and contact bans, such as Japan, South Korea or Sweden, have not experienced a more negative course of events than other countries. Sweden was even praised by the WHO and now benefits from higher immunity compared to lockdown countries.
15. The fear of a shortage of ventilators was unjustified. According to lung specialists, the invasive ventilation (intubation) of Covid19 patients, which is partly done out of fear of spreading the virus, is in fact often counterproductive and damaging to the lungs.
16. Contrary to original assumptions, various studies have shown that there is no evidence of the virus spreading through aerosols (i.e. tiny particles floating in the air) or through smear infections (e.g. on door handles or smartphones). The main modes of transmission are direct contact and droplets produced when coughing or sneezing.
17. There is also no scientific evidence for the effectiveness of face masks in healthy or asymptomatic individuals. On the contrary, experts warn that such masks interfere with normal breathing and may become “germ carriers”. Leading doctors called them a “media hype” and “ridiculous”.
18. Many clinics in Europe and the US remained strongly underutilized or almost empty during the Covid19 peak and in some cases had to send staff home. Numerous operations and therapies were cancelled, including many cancer screenings and organ transplants.
19. Several media were caught trying to dramatize the situation in hospitals, sometimes even with manipulative images and videos. In general, the unprofessional reporting of many media maximized fear and panic in the population.
20. The virus test kits used internationally are prone to errors and can produce false positive and false negative results. Moreover, the official virus test was not clinically validated due to time pressure and may sometimes react positive to other coronaviruses.
21. Numerous internationally renowned experts in the fields of virology, immunology and epidemiology consider the measures taken to be counterproductive and recommend rapid natural immunisation of the general population and protection of risk groups.
22. At no time was there a medical reason for the closure of schools, as children hardly ever transmit the virus or fall ill with it themselves. There is also no medical reason for small classes, masks or ‘social distancing’ rules in schools.
23. The claim that only severe Covid-19 but not influenza may cause venous thrombosis and pulmonary (lung) embolism is not true, as it has been known for 50 years that severe influenza greatly increases the risk of thrombosis and embolism, too.
24. Several medical experts described vaccines against coronaviruses as unnecessary or even dangerous. Indeed, the vaccine against the so-called swine flu of 2009, for example, led to sometimes severe neurological damage and lawsuits in the millions.
25. The number of people suffering from unemployment, depressions and domestic violence as a result of the measures has reached historic record values. Several experts predict that the measures will claim more lives than the virus itself. According to the UN millions of people around the world may fall into absolute poverty and famine.
26. NSA whistleblower Edward Snowden warned that the “corona crisis” will be used for the massive and permanent expansion of global surveillance. The renowned virologist Pablo Goldschmidt spoke of a “global media terror” and “totalitarian measures”. Leading British virologist professor John Oxford spoke of a “media epidemic”.
27. More than 500 scientists have warned of an “unprecedented surveillance of society” through problematic apps for “contact tracing”. In some countries, such “contact tracing” is already carried out directly by the secret service. In several parts of the world, the population is already being monitored by drones and facing serious police overreach.
28. A 2019 WHO study on public health measures against pandemic influenza found that from a medical perspective, “contact tracing” is “not recommended in any circumstances.
See also: Pandemonia Funnies Madebyjimbob
via Science Matters
September 29, 2020 at 01:33PM
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“Unusually severe” spring storm brings snow to New Zealand beaches and travel chaos
Posted on September 29, 2020 Leave a Comment
The storm was “very unusual in how widespread the severe weather is” and was a significant weather event, a release from the Met service said.
The service described the storm as “the worst of the season” and said it was the result of a low-pressure system moving up the country from Antarctica.
The National Institute for Water and Atmospheric Research said parts of the South Island could feel as cold as -20C (-4F) on Monday and Tuesday.
The storm was unusually severe for spring, the Met service said.
Thanks to Laurel for this link
The post “Unusually severe” spring storm brings snow to New Zealand beaches and travel chaos appeared first on Ice Age Now.
via Ice Age Now
September 29, 2020 at 12:24PM
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Posted on September 29, 2020 Leave a Comment
I couldn’t help but laugh when I saw this sign in someone’s yard yesterday. I hope it can also lighten your day.
The post appeared first on Ice Age Now.
via Ice Age Now
September 29, 2020 at 12:24PM
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Great Lakes Drying Up… No, Overflowing… Because Climate Change
Posted on September 29, 2020 Leave a Comment
Guest “because climate change” by David Middleton
From the October 1, 2020 issue of Physics Today… Well, physics the day after tomorrow (good movie title)…
1 OCTOBER 2020 • page 26
The Great Lakes are filled to their brims, with no signs of receding
Experts see the fingerprints of climate change on the lakes’ record high water levels.
David KramerPhysics Today 73, 10, 26 (2020); https://doi.org/10.1063/PT.3.4589
Seven years ago, Ron Wilson’s son was married on the beach in front of his cottage on the eastern shore of Lake Michigan. Were the couple to renew their vows today in the same spot, they’d be standing in nearly two meters of water. The 18-meter-wide beach has vanished, and the lake is now lapping at a steel seawall Wilson erected last winter to keep storms away from his foundation.
[…]
Water levels have always fluctuated on the Great Lakes, but the recent extreme seesawing, particularly on the upper lakes—Superior, Michigan, and Huron—is unprecedented in the century that records have been kept (see charts). Michigan and Huron, which are linked and share the same level, stood at record highs in August, 84 cm above their historic average. The two lakes bottomed out at record lows in 2013. Although a relatively modest 25 cm above average, Superior in 2020 was just 5 cm below its record peak for August set a year ago.
[…]
Signs of climate changeThe past 10 years have been the wettest on record for the Great Lakes watershed. Andrew Gronewold, associate professor for environment and sustainability at the University of Michigan, says the rainy years began well before the 2013 ebb in the upper lakes. An extended period of excess evaporation that started in 1998 more than offset the added precipitation until the polar vortex event in early 2014 caused most of the lakes to freeze over. Since then, water supply has exceeded evaporation, partly because of several especially cold winters, Gronewold says. He adds that the 2014–17 period saw the fastest three-year increase in water levels since record-keeping began.
Donald Wuebbles, professor of atmospheric science at the University of Illinois at Urbana-Champaign, says precipitation over the watershed has risen 10% over the past century and is expected to grow another 10% over the next. Precipitation in the Great Lakes region is increasingly occurring in larger events, researchers say. As a result, more rainfall runs off into streams and rivers feeding the lakes instead of being absorbed in soils. The lakes themselves make up a major portion of the watershed.
“The rate at which precipitation has changed over the past decade simply cannot be explained by historical variability alone,” says Gronewold. “The best explanation is a warming atmosphere and warming global temperature.”
[…]
The article provides this USACE chart of historical lake levels…
The caption in the article must be a typo…
Water levels on the Great Lakes have fluctuated irregularly over the past century. The peaks and troughs on Lakes Michigan and Huron have been especially pronounced. From a record low in 2013, they have surged to record highs this year. (US Army Corps of Engineers.)
Michigan-Huron appears to have been just as low as 2013 in 1965-1966 and within 1 foot of that low in the mid-1920’s and mid-1930’s. The “record highs this year” don’t look any higher than 1987 and the mid-1970’s, mid-1950’s and 1930 appear to have been within 1 foot of those record highs. I
What does the US Army Corps of Engineers (USACE) data show?
The peaks and troughs on Lakes Michigan and Huron have been especially pronounced. From a record low in 2013, they have surged to record highs this year.
This year isn’t over. The most recent full year of USACE records is 2019. Lakes Michigan-Huron set no monthly record highs in 2019 and only one record monthly low in 2013. 11 monthly record highs were set in 1986 and 1 in 1987. Most of the Great Lakes monthly record highs were set in the mid-1980’s. 10 of the monthly record lows for Michigan-Huron were set in 1964. The vast majority of record monthly lows for the other lakes were set in the 1920’s and 1930’s.
What’s really funny? They tell us that climate change caused these record highs and lows and will make the seesawing worse… But…
Longer term, it’s anyone’s guess where lake levels are headed. The range of possibilities in the six-month forecasts by the US Army Corps of Engineers is so broad in the latter months as to be of little use, researchers say.
via Watts Up With That?
September 29, 2020 at 12:05PM
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MetOffice, IPCC Climate Scientist Prof. Richard Betts Misunderstood Science Behind Drying Forests
Posted on September 29, 2020 Leave a Comment
Just recently Anthony Watts posted an article on wildfires penned by Paul Homewood. Lately alarmists have been blaming the active forest fire season on global warming. They warn that warmer temperatures will lead to more wildfires.
Is it so?
First it’s important to note that warmer temperatures don’t necessarily lead to more drought and wild fires. For example in 2018 I reported here how the Sahara desert has shrunk by a whopping 700,000 sq km over the recent decades, even though this is a region with very warm temperatures.
Also we know that the earth’s surface has often been drier during cooler times.
Moreover, meteorologist Chris Martz here explains that long-term forest fires have not been getting worse in the USA, and “are nowhere near as bad as they used to be”.
U.S. wildland fire counts by year since 1926 (Figure 5a – left) and U.S. wildland fire burn acreage over that same time period (Figure 5b – right).
Climate scientist doesn’t understand why forests dry
On the WUWT article I commented at Twitter that when it comes to wildfires, temperature is not a factor behind them, to which University of Exeter, Met Office, IPCC. UK Climate Prof. commented:https://platform.twitter.com/embed/index.html?dnt=true&embedId=twitter-widget-0&frame=false&hideCard=false&hideThread=false&id=1309782180365840384&lang=de&origin=https%3A%2F%2Fwordpress.com%2Fread%2Ffeeds%2F9078981%2Fposts%2F2938605052&theme=light&widgetsVersion=219d021%3A1598982042171&width=550px
Most laypersons of course believe that higher temperatures “dry out” surfaces and fuel faster, as climate expert Prof. Richard Betts obviously did. After all, we use a hair dryer to dry our hair more quickly, or throw our wet laundry in the dryer. So most people think that it’s the high temperature that is doing the drying. But that’s not quite how it works.
Astonishing misunderstanding of fundamental science
We can forgive a layperson for misunderstanding this fundamental science, but it is spectacularly astonishing that a supposedly distinguished climate professor such as Prof. Betts would misunderstand it. How on earth could someone with such a fundamental misunderstanding be expected to explain climate to us, let alone model it?
Or perhaps, in his desire to be dramatic, he got sloppy and miscommunicated it.
It’s the relative humidity, stupid!
There’s only one factor behind drying forest, grassland, ground surface: the relative humidity of the air next to the surface (difference temperature and dew point) and precipitation.
If the air has a very high relative humidity, then drying will take a long time, no matter what the temperature is. If temperature was the main factor behind drying, then places like the Amazon, Congo or Southeast Asian rainforests would have dried up and burned long ago. But they haven’t.
In fact the planet’s biggest deserts are the Arctic and Antarctic. Last I checked they are still cooler than the Amazon.
It’s not the temperature!
To help drive the point home to the MetOffice climatologist, veteran meteorologist Jörg Kachelmann at Twitter joined in, asking Prof. Betts:https://platform.twitter.com/embed/index.html?dnt=true&embedId=twitter-widget-1&frame=false&hideCard=false&hideThread=false&id=1309804363360227331&lang=de&origin=https%3A%2F%2Fwordpress.com%2Fread%2Ffeeds%2F9078981%2Fposts%2F2938605052&theme=light&widgetsVersion=219d021%3A1598982042171&width=550px
Remember, these are the scientists who provide the input into the climate models.
Correct would be to say: Warming may lead to lower air humidity and less precipitation, which in turn increases the risk of wildfires. But then again, they also like to tell us that warming leads to more rainfall. A lot of confused scientists out there.
By P Gosselin on 29. September 2020
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Sea Ice Extent (Global Antarctic and Arctic) – Day 272 – 2020
Posted on September 29, 2020 Leave a Comment
PUBLISHED ON September 29, 2020
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Colder “climate change” blamed for excess deaths in Word War I
Posted on September 29, 2020 Leave a Comment
From the American Geophysical Union.
WASHINGTON—Scientists have spotted a once-in-a-century climate anomaly during World War I that likely increased mortality during the war and the influenza pandemic in the years that followed.
Well-documented torrential rains and unusually cold temperatures affected the outcomes of many major battles on the Western Front during the war years of 1914 to 1918. Most notably, the poor conditions played a role in the battles of Verdun and the Somme, during which more than one million soldiers were killed or wounded.
The bad weather may also have exacerbated the Spanish flu pandemic that claimed 50 to 100 million lives between 1917 and 1919, according to the new study. Scientists have long studied the spread of the H1N1 influenza strain that caused the pandemic, but little research has focused on whether environmental conditions played a role.
In a new study in AGU’s journal GeoHealth, scientists analyzed an ice core taken from a glacier in the European Alps to reconstruct climate conditions during the war years. They found an extremely unusual influx of air from the North Atlantic Ocean affected weather on the European continent from 1914 to 1919. The incessant rain and cold caused by this influx of ocean air hung over major battlefields on the Western Front but also affected the migratory patterns of mallard ducks, the main animal host for H1N1 flu virus strains.
Mallard ducks likely stayed put in western Europe in the autumns of 1917 and 1918 because of the bad weather, rather than migrating northeast to Russia as they normally do, according to the new study. This kept them close to military and civilian populations and may have allowed the birds to transfer a particularly virulent strain of H1N1 influenza to humans through bodies of water.
The findings help scientists better understand the factors that contributed to making the war and pandemic so deadly, according to Alexander More, a climate scientist and historian at the Harvard University/Climate Change Institute, associate professor of environmental health at Long Island University and lead author of the new study.
“I’m not saying that this was ‘the’ cause of the pandemic, but it was certainly a potentiator, an added exacerbating factor to an already explosive situation,” More said.
“It’s interesting to think that very heavy rainfall may have accelerated the spread of the virus,” said Philip Landrigan, director of the Global Public Health Program at Boston College who was not connected to the new study. “One of the things we’ve learned in the COVID pandemic is that some viruses seem to stay viable for longer time periods in humid air than in dry air. So it makes sense that if the air in Europe were unusually wet and humid during the years of World War I, transmission of the virus might have been accelerated.”
War and weather
The rainy, cold, muddy landscapes of the Western Front are well documented by historians. Poet Mary Borden described it as “the liquid grave of our armies” in her poem “The Song of the Mud” about 1916’s Battle of the Somme.
Historical accounts of early battles in France describe how the intense rain affected British, French and German troops. Newly dug trenches and tunnels filled with rainwater; muddy fields slowed the movement of troops during the day; and cold nighttime temperatures caused thousands to endure frostbite. However, little research has been done on the environmental conditions that may have caused the torrential rains and unusual cold.
In the new study, More and his colleagues reconstructed the environmental conditions over Europe during the war using data from an ice core taken from the Alps. They then compared the environmental conditions to historical records of deaths during the war years.
They found mortality in Europe peaked three times during the war, and these peaks occurred during or soon after periods of cold temperatures and heavy rain caused by extremely unusual influxes of ocean air in the winters of 1915, 1916 and 1918.
“Atmospheric circulation changed and there was much more rain, much colder weather all over Europe for six years,” More said. “In this particular case, it was a once in a 100-year anomaly.”
The new ice core record corroborates historical accounts of torrential rain on battlefields of the Western Front, which caused many soldiers to die from drowning, exposure, pneumonia and other infections.
Interestingly, the results suggest the bad weather may have kept mallard ducks and other migratory birds in Europe during the war years, where they could easily transmit influenza to humans by water contaminated with their fecal droppings. Mallard ducks are the main animal reservoir of H1N1 flu viruses and as many as 60 percent of mallard ducks can be infected with H1N1 every year. Previous research has shown that migratory patterns of mallards and other birds are disrupted during bouts of unusual weather.
“Mallards have been shown to be very sensitive to climate anomalies in their migration patterns,” More said. “So it is likely is that they stayed put for much of that period.”
The first wave of H1N1 influenza infection in Europe occurred in the spring of 1918, most likely originating among allied troops arriving in France from Asia in the fall and winter of 1917, according to previous research. The new study found the deadliest wave of the pandemic in Europe began in the autumn of 1918, closely following a period of heavy precipitation and cold temperatures.
“These atmospheric reorganizations happen and they affect people,” More said. “They affect how we move, how much water is available, what animals are around. Animals bring their own diseases with them in their movements, and their migrations are due to the environment and how it changes, or how we change it.”
“I think it’s a very credible, provocative study that makes us think in new ways about the interplay between infectious diseases and the environment,” Landrigan said.
###
Paper title:
“The impact of a six-year climate anomaly on the ‘Spanish Flu’ Pandemic and WWI” and is freely available. Download a PDF copy of the paper here.
Multimedia files accompanying this press release can be found here:
https://drive.google.com/drive/folders/1pje08yi5GZwevsozA6MV6CvpSyNUezYU
via Watts Up With That?
September 29, 2020 at 08:47AM
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La Niña underway in the tropical Pacific, says Australia’s BoM
Posted on September 29, 2020 Leave a Comment
Source: Bureau of Meteorology — ENSO Outlook [updated every 2 weeks]
La Niña underway in the tropical Pacific
LA NIÑALA NIÑAALERTWATCHINACTIVEWATCHALERTEL NIÑOENSO Outlook
The Bureau’s ENSO Outlook has moved to LA NIÑA, indicating La Niña is established in the tropical Pacific. All surveyed international climate models indicate this La Niña will persist until at least January 2021.
While models agree La Niña will continue well into summer 2020–21, around half the models predict a strong event, while 3 of 8 models suggest moderate strength. Overall, models do not currently anticipate this event will be as strong as the La Niña of 2010–12, which was one of the four strongest La Niñas on record. The strength of La Niña impacts on Australia are often related to the strength of the event.
Central and eastern tropical Pacific Ocean sea surface temperatures exceed La Niña thresholds (0.8 °C below average) and atmospheric indicators, including the Southern Oscillation Index (SOI), trade winds and cloud, are also at La Niña levels.
In the Indian Ocean, the latest values of the Indian Ocean Dipole (IOD) index have again gone into negative dipole territory. Five of the 6 surveyed models indicate the IOD will be negative for October, and three models continue negative IOD values into November.
Both La Niña and negative IOD typically increase the chance of above average rainfall across much of Australia during spring. Above average summer rainfall is also typical across eastern Australia during La Niña. Current climate outlooks indicate the remainder of 2020 will be wetter than average across the eastern two thirds of Australia.
The Southern Annular Mode (SAM) is expected to be neutral or weakly positive for the coming weeks. La Niña tends to favour positive SAM during spring and summer, which typically enhances the wet signal in the east.
The Madden–Julian Oscillation (MJO) is currently weak or indiscernible, but may increase in strength as it moves from the Maritime Continent into the Western Pacific Ocean.
Climate change is also influencing the Australian climate. Australia’s climate has warmed by around 1.4 °C since 1910, while southern Australia has seen a 10–20% reduction in cool season (April–October) rainfall in recent decades.
– – –
La Niña is a coupled ocean-atmosphere phenomenon that is the colder counterpart of El Niño, as part of the broader El Niño–Southern Oscillation (ENSO) climate pattern. – Wikipedia
via Tallbloke’s Talkshop
September 29, 2020 at 08:40AM
