Archives par mot-clé : La Nina

unclassified

Are ENSO Regime Changes Connected To Major Climate Shifts? Are We Tipping To Cooling?

by P. Gosselin, Apr 19, 2023 in NoTricksZone

We’ve had a La Niña for nearly three years. But now it has officially ended, and ENSO has moved into its neutral phase, the “La Nada”.[1] The La Niña event lasted three winters in a row, something that has only occurred twice before in modern times: 1973–1976 and 1998–2001. Both of these followed in response to a very strong El Niño.

The La Niña that has now ended, on the other hand, came after the more neutral winter of 2019/20.

Figure 1. Number of months with each ENSO phase for five-year periods from 1950 – 2023

The number of months that we have had each ENSO phase in the last 74 years is shown in Figure 1. The La Niñas are more frequent than the El Niños. Interestingly, the opposite was true during the rapid warming we had from 1975 – 1999, when El Niños were more common. But then it reverts back again around 1998/99. Is there a pattern here?

It is established in climate science that the climate underwent a profound shift in 1976/77, related to the ocean currents.[2] In IPCC AR4, they write: “The 1976–1977 climate shift in the Pacific, associated with a phase change in the PDO from negative to positive, was associated with significant changes in ENSO evolution.” The Pacific Decadal Oscillation (PDO) shifted from a ‘cold’ to a ‘warm’ phase during these two years.[3] The ENSO also became dominated by the El Niño phase, which is characterized by warmer temperatures.[4] These changes affected the global climate, and a rapid warming began.

But what happened in the years just before 2000? As seen in Figure 1, ENSO reverts to being dominated by the ‘colder’ La Niña at that time.

Figure 2. The PDO index according to NOAA/ESRL.

Interestingly, the PDO also reverts to its cold phase in 1998–1999.

Are we seeing a shift to a colder phase in the climate here?

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climate-debate

Scientists Warn of a Rare Third Year La Nina

by INSTITUTE OF ATMOSPHERIC PHYSICS, CHINESE ACADEMY OF SCIENCES,  Oct 21, 2022 in WUWT

El Niño–Southern Oscillation (ENSO) is an irregular periodic variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean that affects the climate of much of the tropics and subtropics. This natural phenomenon is important to study because of the socioeconomic impacts it can have on matters such as food security, agricultural production, human health and water resources, to name but a few.

With its strong preference to peak during boreal winter and rapidly decay in spring (known as “phase-locking”), and quasi-periodic oscillations of 2–7 years, historically, ENSO rarely maintains for long in either its cold phase (La Niña) or warm phase (El Niño). However, since the turn of the current century, three instances of so-called “double dip” La Niña events have occurred, in 2007–09, 2010–12 and 2020–22.

This succession of double-dip La Niña events is intriguing enough in itself; but now, based on updated data from several organizations issued in April 2022, it seems that the current event is likely to continue through the boreal summer and fall of 2022, suggesting a strong possibility of a third-year La Niña lasting from 202023.

“This would be the first third-year La Niña since the 1998–2001 event, which was the only such event observed since 1980,” explains Dr Xianghui Fang from Fudan University, China.

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See also : Alarmist Scientist Tim Flannery’s Drought Prediction Contradicted… “Heavy Rainfalls” 3 Years In a Row

climate-debate, Cooling

La Nina is Not Going Away. What Does This Mean for This Summer’s Weather?

by C. Mass, May 16, 2022 in WUWT

It is now clear that La Nina is not going away, and may hang around into next winter.  

Cold water is entrenched over the central and eastern tropical Pacific (the definition of La Nina) and the latest forecast model runs suggest a continuation into fall.

Several of you have asked:   what does this imply for our summer weather?

Let me tell you.

But first, the bottom line:   the summer effects of La Nina are modest, but will push the western side of our region towards cooler than normal conditions.

The Impacts

During La Nina years, sea surface temperatures off the West coast are usually cooler than normal, and those cooling effects spread inland.

To illustrate, here is the sea surface temperate difference from normal for the summer months (May through September) for La Nina years.    Blue colors are cooler than normal.

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climate-debate

Is the third La Niña on the way?

by Dr R. Maue, Apr 16, 2022 in NoTricksZone

It was supposed to be a groundbreaking forecast, the early prediction of the weather phenomena El Niño and La Niña. Both affect the weather in very different ways.

It would have been so nice to know a year in advance what conditions would prevail at a later date. On November 4, 2019, the Potsdam Institute for Climate Impact Research published what was held as groundbreaking news. Thanks to its new algorithms and a lot of computing power, it was now possible to predict an El Niño or a La Niña a long time in advance. The hit rate was supposed to be 80%.

Unfortunately, one year later exactly the opposite of what was predicted in fact happened, the German Klimaschau reported. Science is settled? Well, maybe not.

Since then, things have been quiet about these PIK long-term forecasts. The US agency NOAA is much more cautious, both in terms of the long term and the probability of occurrence. Perhaps they don’t have as good algorithms and the computing power that Potsdam has? In any case on Twitter, US meteorologist Ryan Maue sees a good chance that a third will follow the two recent consecutive La Niñas.

The last time this happened was 22 years ago at the turn of the millennium.

 

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climate-debate

The Sun’s climate role confirmed

by D. Whitehouse, April 6, 2021 in GWPF

“The scientific community has been unclear on the role that solar variability plays in influencing weather and climate events here on Earth. This study shows there’s reason to believe it absolutely does and why the connection may have been missed in the past.”

Top: Six-month smoothed monthly sunspot number from SILSO.  Bottom: Oceanic El Niño Index from NOAA. Red and blue boxes mark the El Niño and La Niña periods in the repeating pattern. Source: Climate Etc, September 2019

If you ask most climate scientists, they will tell you that the Sun’s small variability is unimportant when it comes to influencing climate. They may have to change their minds if a new line of research holds up. It seems that solar variability can drive climate variability on Earth on decadal timescales (the decadal climatic variability that Michael Mann recently ‘proved’ doesn’t exist). That’s the conclusion of a new study showing a correlation between the end of solar cycles and a switch from El Nino to La Nina conditions in the Pacific Ocean. It’s a result that could significantly improve the predictability of the largest El Nino and La Nina events, which have several global climate effects.

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climate-debate

New study ties solar variability to the onset of decadal La Nina events

by C. Rotter, April 5, 2021 in NATIONAL CENTER FOR ATMOSPHERIC RESEARCH/UNIVERSITY CORPORATION FOR ATMOSPHERIC RESEARCH

A new study shows a correlation between the end of solar cycles and a switch from El Nino to La Nina conditions in the Pacific Ocean, suggesting that solar variability can drive seasonal weather variability on Earth.

If the connection outlined in the journal Earth and Space Science holds up, it could significantly improve the predictability of the largest El Nino and La Nina events, which have a number of seasonal climate effects over land. For example, the southern United States tends to be warmer and drier during a La Nina, while the northern U.S. tends to be colder and wetter.

“Energy from the Sun is the major driver of our entire Earth system and makes life on Earth possible,” said Scott McIntosh, a scientist at the National Center for Atmospheric Research (NCAR) and co-author of the paper. “Even so, the scientific community has been unclear on the role that solar variability plays in influencing weather and climate events here on Earth. This study shows there’s reason to believe it absolutely does and why the connection may have been missed in the past.”

The study was led by Robert Leamon at the University of Maryland-Baltimore County, and it is also co-authored by Daniel Marsh at NCAR. The research was funded by the National Science Foundation, which is NCAR’s sponsor, and the NASA Living With a Star program.

Applying a new solar clock

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better to know...?

After nearly a decade away, La Niña weather system is back…

by C. Rotter, nov 1, 2020 in WUWT

Many will be familiar with El Niño – the ocean-warming phenomenon that affects global weather patterns – but how about La Niña, which is linked to cooler sea temperatures?

According to the World Meteorological Organization (WMO), La Niña is back in the central and eastern equatorial Pacific Ocean, after nearly a decade’s absence.

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UNDP/Joe HitchcockThe low-lying island Pacific Ocean nation, Tuvalu, is particularly susceptible to a rise in sea levels caused by climate change.    29 October 2020Climate Change

This is expected to result in sea surface temperatures between two and three degrees Celsius cooler than average, said Dr. Maxx Dilley, Deputy Director in charge of Climate Services Department at WMO.

“These coolings of these large ocean areas have a significant effect on the circulation of the atmosphere that’s flowing over them. And the changes in the atmosphere in turn affect precipitation patterns around the world.”

Uneven effects

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climate-debate

Low Solar Activity Points To Colder Than Normal 2020/21 European Winter

by P. Gosselin, Oct 16, 2020 in NoTricksZone

SnowFan here reports on the latest winter forecasts for the 2020/21 Europe winter. History and statistics show Europe could be in for a frosty winter. 

Currently a significant La Nina is shaping up, and history shows that these events in the Pacific have an impact on Europe’s winters:

 

 

The NOAA reanalysis above shows the temperature deviations (left) and for precipitation (right) from the WMO average 1981-2010 during the six La Niña years of winter in Europe. Large parts of Europe have average temperatures and precipitation is distributed differently, with Germany being slightly drier overall than the WMO average. Is a 2020/21 winter in Germany under La Niña conditions shaping up to have average temperatures and slightly less humidity?

Strong winter-solar correlation

A more important factor determining winter in Europe may be solar activity. Data from the German DWD national weather service since 1954 show a remarkable higher frequency of cold winters in times of low solar activity, such as we are now in the midst of.

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climate-debate

The “Warmest September Ever” Is A Myth… Cooler Times Likely Ahead As NASA Foresees Strong La Nina…

by P. Gosselin, Oct 9, 2020 in NoTricksZone

Our friend “SnowFan” here looks at the claims that September 2020 was the warmest ever recorded. It turns out that other measurement advanced satellites don’t agree.

According to the much ballyhooed data, temperatures in Europe in September this year were on average 0.2 degrees Celsius higher than in the previous record September 2018. The service providing the data is part of the European earth observation program Copernicus.

But the satellite data from the UAH and RSS both agree that this is not really the case!

 

Above the global satellite data from UAH (left) and from RSS (right) in the tables clearly clearly show the monthly deviations from the WMO mean 1981-2010 (UAH) and from the climate mean 1979-1998 (RSS): September 2020 was not the warmest since satellite measurements began in 1979. At UAH, September 2019 was slightly warmer while at RSS even September 2017 was warmer.

Strong La Nina may be in the works

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better to know...?, climate-debate

LA NINA HAS ARRIVED: NEAR-TERM COOLING

by Cap Allon, Oct 11, 2020 in Electroverse

The following article is written by Bob Hoye of www.pivotaladvice.com.

Last week, the Global Warming policy Forum headlined “La Nina Is Here”. Why the headline? Because the warming El Nino is over and the change to the La Nina represents cooling. Like seasonal and actual climate change, it is a regular event. Which in physics means logical and predictable. And some cooling is showing up in various charts. Well, in those not altered by promoters of AGW.

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unclassified

El Nino & Arctic Warming In the 1930s

by P. Homewood, April 5, 2020 in NotaLotofPeopleKnowThat

Just following up on Joe Bastardi’s article yesterday about El Ninos and Arctic warming, it is worth looking at longer term trends.

Below is the chart of the MEI, with red indicating El Ninos and blue La Ninas.:

Extended Multivariate ENSO Index

https://www.esrl.noaa.gov/psd/enso/mei.ext/

As we can see, the period 1925 to 1945 was dominated by powerful El Ninos. This of course was also the time of great warming in the Arctic, known as “The Warming in The North”, when temperatures across much of the Arctic were as high as they are now.

During the 1950s, a much colder climate took over in the Arctic, until it became warmer again in the 90s. This was also a period when La Ninas dominated.

Coincidence?

The climate in the Arctic is also very well correlated with the Atlantic Multidecadal Oscillation (AMO):

Continuer la lecture de El Nino & Arctic Warming In the 1930s →

climate-debate

The La Nina Pump

by Willis Eschenbach, July 16, 2018 in WUWT

Sometimes a chance comment sets off a whole chain of investigation. Somewhere recently, in passing I noted the idea of the slope of the temperature gradient across the Pacific along the Equator. So I decided to take a look at it. Here is the area that I examined.

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I’ve written about this temperature gradient before, in a post called The Tao of El Nino. If you take time to read that post, this one will make more sense. …

climate-debate

HOW WARM WILL 2018 BE?

by Dr David Whitehouse, June 06, 2016 in GWPF

As far as global temperature goes it’s been a warmish start to the year, though not exceptional. This has led Carbon Brief in its three-monthly “state of the climate” report to predict that this year “is likely” to be as warm as the fourth warmest year since records began about 150 years ago. They say it could be as high as the second or as low as the 12th warmest.

Carbon Brief says, “The first three months of 2018 can give some sense of what to expect for the entire year.” But being based on a quarter of this year’s monthly measurements it could be described as either bold or foolish. Because the prediction is made without a good understanding of what has been happening to the global temperature in the past months it is probably more of the latter.

Nowhere is the Carbon Brief prediction is there any analysis of why 2018 got off to a warm start. Look towards the  Tasman Sea that has been adding to global temperatures since late 2017.

The water temperature in the Tasman Sea is well above normal –  6° C more than average for the start of December. New Zealand’s summer was the hottest on record, Tasmania had its hottest November-January on record. It was exceptionally warm on both sides of the Tasman, more than two degrees above average in December and part of January.

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