California Monarchs — Too Much Activism

Opinion by Kip Hansen  — 24 September 2022

The marvelous mysterious Monarch Butterfly has been getting too much of the wrong type of help in California.  Honestly, this does not surprise me, having been born, raised and educated there.   The state of California, whose state flag bears the words “California Republic”, has been slipping off the left edge of the political spectrum since the 1960s and like all things on slippery slopes, the state and its politics continue to slide, faster and faster,  affecting more and more areas of public and private life.

The latest little bit of madness there is a misguided effort to help the Western Monarch population by the banning the sale of tropical milkweed plants by several counties in the state.  Milkweed plants are an absolute necessity for Monarch butterflies to reproduce. 

The Western Monarch Migration (see down-page section on the Western Migration) has been seeing a very steep decline over the last couple of decades.  There are lots of theories as to the cause, from Global Warming through insecticides and onto the mowing of highway verges – including “all of the above”. 

The overwintering population was approaching  zero in the winter of 2020-2021 and then, in 2021-2022 skyrocketed with “an over 100-fold increase from the previous year’s total of less than 2,000 monarchs and the highest total since 2016” with the monarch census reporting over 250,000 monarchs in roosts along the California coastline. 

Truthfully, neither the sharp decline or the unbelievable (partial) recovery has been explained to anyone’s satisfaction.  It seems unreasonable that a population as small as 2,000 in the spring of 2021 could then produce the 250,000 overwintering Monarchs in a single season.  But that is precisely what appears to have happened.

Now we find ourselves — and the Monarchs find themselves — in the summer of 2022 with the environmental activists pitching in to help the California monarchs by banning the sale of tropical milkweeds by nurseries in Marin, Contra Costa, San Mateo and Ventura counties.  Why ban the sale of garden plants that monarchs need to reproduce? 

Because the California Department of Agriculture recategorized it as a noxious weed.  Of course, tropical milkweed is not a weed and it is not noxious.  There is something about the tropical milkweeds that is true however – it is a perennial.  That means it does not die off every winter but stays alive and re-greens and blooms the next year, especially in warmer climates like California and the American South.  And, because it does not die off, it is possible for these prettier varieties to “host to a protozoan parasite of monarch butterflies (Danaus plexippus) called Ophryocistis electroscirha (OE), which are carried on adult monarchs as they migrate. The dormant OE spores are then deposited on the leaves of the tropical milkweed and infect caterpillars that eat the plant. CDFA (California Department of Food and Agriculture) said that OE infections have been linked to lower migration success, reduction in body mass, lifespan, mating success, and flight ability.” [ source ]  

It is not that there is anything special about the tropical milkweeds that is different than the native milkweeds in regards to hosting the protozoan parasites…except that when native milkweed’s tops (above ground portion of the plant) die at the end of the season, the parasites on them die and the next year’s crop of native milkweeds that come up from seed or rhizomes start out not infected – though they soon become so, whereas the tropicals, in mild climates, continue to grow through the warmer winters hosting the protozoans continuously.

Tropical Milkweeds

So the whole banning of these beautiful tropical milkweeds and distributing native milkweeds to take their place is based on that little months-long lag. 

What do the entomologists (as distinguished from activists) say?  :

“Arthur Shapiro, a UC Davis professor who has studied monarch butterflies for the past six decades, described the rationale behind the bans as “hogwash.”

And

“Hugh Dingle, a retired University of California at Davis entomology professor who has studied monarch butterfly migration for more than two decades, said the bans are “basically a wasted effort” and that the focus should be on larger threats such as pesticide and herbicide use. All species of milkweed carry parasites that can affect monarch populations, Dingle said.

“Planting milkweed of any kind in your garden — tropical or native — there’s unlikely to be enough of it to do any good, but it’s not going to do any harm,” Dingle said. “If you like monarchs in your garden, go ahead and plant it. I didn’t want the information on tropical milkweed to cause the ladies of Marin (county) to go running out to their gardens and dig out all of their tropical milkweed because it’s supposedly bad for butterflies. It’s not.”

One more:

“David James, an associate entomology professor at Washington State University who has studied monarch butterfly breeding and migration in the [San Francisco] Bay Area, said there is a case to be made about the tropical milkweed as being a vital resource for the monarchs in a changing climate.

“The Monarch is adapting to our warming climate and in doing so a proportion of the population is now spending winters breeding in urban near-coastal California,” James wrote in an email. “And what host plants are there? Some limited native milkweeds but a whole bunch of tropical milkweed! Taking tropical milkweed away will just make it harder for the population to survive.” [ source for all quotes above ]

Say what?  California’s entomologists quoted all disagree with the ban and at least one says the ban will have negative, not positive, effects.  So where did the idea come from?

It comes from the Xerces Society, “Protecting the natural world through the conservation of invertebrates and their habitats.” Which supplied their expert’s opinion:

“Stephanie Frischie, an agronomist and native plant specialist with the Xerces Society, said there are many purported causes for the decline in monarch butterfly populations. The buildup of pathogens on the tropical milkweed during the winter months is one of these pressures, which can be prevented by having residents plant the readily available native milkweed.

“There is really no single cause and therefore there is no silver bullet to solving monarch decline,” Frischie said. “Where we are right now with current research, there are concerns with tropical milkweed with disease and interrupting migratory behavior. In general, as a conservation organization, we support native plants in their native ranges as habitat for invertebrates.”

The Xerces Society’s concerns have won out in the political battle over the more scientifically-based opinions of monarch-specific experts from academia. 

Will it make a difference?  Will it improve the lot of the Western Migration of Monarchs?  Will it harm the migrating population?  No one really knows.  No one knows because they do not know what — if anything specific — is causing the shifts in that particular segment of the overall population of Western Monarchs. 

“The overall population of Western Monarchs?” you might ask.  Yes, you see, not all the Monarchs living west of the Rocky Mountains migrate to the coast and overwinter in collective roosts.   Many, and no one knows how many monarchs we are talking about, migrate to the urban and suburban neighborhoods along the coast of southern California, continuing to live, breed, and die in their normal pattern and not entering a period of  reproductive diapause or forming collective roosts, like their “migrating and overwintering” fellows. 

The environmental entomological activists are not trying to save the Western Monarchs, they are trying to save the behavior, the phenomenon,  known as the Western Monarch Migration.  To the left of the word SUMMER we see the western migration as red and yellow arrows.  You can see that some migrate to the same areas in Mexico as the Eastern Monarchs.  Others, from the deserts of southern California and western Arizona migrate to and from the southern-most coasts of California and do not form overwintering roosts at all.  According to David James (quoted above) some may even just move to coastal Marin County for the winter and carry on living and breeding. 

It is mostly those flying down from eastern Washington, eastern Oregon , northern and central California  and the western slopes of the Rocky Mountains that form overwintering roosts along the coasts of California, north of Ventura.

It is a matter of opinion as to whether or not the Western Migration is something that must be saved, that must be preventing from disappearing. There is not now, nor has there been in the past, any danger of the Monarchs west of the Rockies going extinct.  The only real possibility is that they will cease that particular behavior. 

Bottom Lines:

1.  Monarch Butterflies are found in many parts of the world and it is extremely unlikely that they will go extinct.  

2.  The Monarchs west of the Rockies in the United States are going strong but many of them have ceased the pattern of winter diapause and associated roosting – the phenomenon called the Western Monarch Migration. 

3.  It is extremely unlikely that the population of monarchs west of the Rockies will go extinct but rather highly possible that the general population will continue to occupy suitable niches in urban and suburban coastal California during the mild California winters and then disperse out into the rest of their western range each Spring, foregoing the diapause stage.

4.  Efforts by activist groups to force their human preferences on the Monarchs are not likely to be successful particularly because we do not understand the causes of the changes we are seeing.

5.  Finally, the banning of tropical milkweeds is not only unnecessary, but is likely to have the opposite of intended effect, harming the Monarch population instead of helping it. 

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Author’s Comment:

Like many other interventions in the past, taking action before understanding the causes of what seem to be undesirable changes in some part of the natural world, this intervention will either fail to improve things or will actually make some things worse.  We never seem to learn this lesson.

And while the Xerces Society’s recommendation on this topic was undoubtedly been made in good faith, the California policy setters should have listened to a wider variety of experts from their own universities, those that have studied this particular species, in this particular area and have concerned themselves with this particular phenomenon for decades before recommending any action. 

Even time will not tell in this case.   There are far too many variables to be able to determine success or failure of this odd little decreed interference in the natural order.

In the end, I ask that you be a Butterfly Friend.  Plant butterfly friendly flower gardens, plant milkweeds — yes, preferably but not exclusively, native milkweeds, though even this recommendation depends on where you live — and participate in public meeting that advise state and county road maintenance crews to leave stands of roadside milkweed rather than mowing them. 

Thanks for reading.

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September 24, 2022 at 04:24PM

Trend Change? Greenland Ice Mass Loss Has Been Decelerating Since 2012

Greenland’s Ice Mass Balance 2021/22

By

Autumn has begun. Time for the Greenland mass balance.

We have digitized the Polar Portal’s graph of the accumulated surface mass balance and have come up with a value of 467 Gt. That’s 100 Gt or 27% above the 1981…2010 mean! Together with the melting of icebergs (assuming the value of the previous year, which was already 10% more than that of 2020 ) this results in approximately the representation below, which was included in the publication until the report 2020.

In 2021, one has probably omitted for reasons, perhaps the jump was difficult to explain by the calving of icebergs?

The total mass balance is very likely -100 Gt. An “accelerated” thawing of the Greenland ice sheet is not to be recognized. If one accumulates the mass loss, one sees the “braking” very nicely. Acceleration occurred until 2012.

Accumulated Greenland ice loss in gigatonnes since 1986.

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September 24, 2022 at 12:16PM

Pelosi calls it! Celebrate! The ‘climate crisis’ is officially over! Pelosi Declares ‘We Saved the Planet’ w/ pork-barrel federal spending bill! — But wait…Not so fast…

From Climate Depot

House Speaker Nancy Pelosi on Sept 22, 2022: “We saved the planet.  We’re saving the planet with record $360 billion to save the planet, generating jobs and cleaner air and cleaner water and jobs and security for our country.”

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Climate Depot’s Morano response: Yea! Now can we go back to driving cars, eating meat and using appliances, and controlling our own home thermostats?!

Cheers! Take a moment to let it sink in! With the Inflation Reduction Act going into law, the long battle to fight ‘global warming’ has finally been solved! Let the good times roll! “Roll out the barrel, we’ll have a barrel of fun. Roll out the barrel, we’ve got the blues on the run. Zing boom tararrel, ring out a song of good cheer!”

BUT WAIT…The pork-barrel Inflation Reduction Act will not even impact global CO2 levels, let alone the climate!

See:Analysis: Biden’s 50% emissions reduction target for 2030 (if achieved) would have a ‘nearly unmeasurable’ impact on overall global CO2 emissions&

Statistician Bjorn Lomborg: Biden’s IRA climate bill will ‘do almost nothing for the global temperature…even by end of century’ – ‘Will reduce temps by less than 1 thousandth of a degree F by the end of the century’

We have also heard these premature alleged climate-solving declarations before. But the ‘climate crisis never seems to get ‘solved.’ See:

Flashback: 2015: World leaders hail ‘historic’ Paris climate deal as ‘major leap for mankind’ – U.N. Secretary-General Ban Ki-moon: “History will remember this day,” Ban Ki-moon said after the pact was gaveled through to thunderous applause. “The Paris agreement on climate change is a monumental success for the planet and its people.”

Al Gore on UN Paris pact in 2015: “Years from now, our grandchildren will reflect on humanity’s moral courage to solve the climate crisis and they will look to December 12, 2015, as the day when the community of nations finally made the decision to act,” Gore said.

By: Marc Morano – Climate DepotSeptember 23, 2022 12:56 PM with 0 comments

https://www.cnsnews.com/blog/craig-bannister/nancy-pelosi-declares-we-saved-planet

By Craig Bannister

“We saved the planet,” House Speaker Rep. Nancy Pelosi (D-Calif.) declared Thursday.

Pelosi made the claim at her weekly press briefing, touting the passage of Democrats’ $360 billion Inflation Reduction Act:

“And we saved the planet.  We’re saving the planet with record $360 billion to save the planet, generating jobs and cleaner air and cleaner water and jobs and security for our country.”

“But I’m not walking away from $360 billion in support for saving the planet for our children and, again, lower prescription drug prices for our families.”

https://www.mrctv.org/embed/574124

Pelosi has had her heart set on planet-saving for more quite some time. Back in 2008, a year and a half after taking power as speaker of the House, Pelosi announced her intention as she staunchly rejected Republicans’ efforts to make America more energy independent.

“I’m trying to save the planet; I’m trying to save the planet,” Pelosi insisted, as Politico reported at the time:

“With fewer than 20 legislative days before the new fiscal year begins Oct. 1, the entire appropriations process has largely ground to a halt because of the ham-handed fighting that followed Republican attempts to lift the moratorium on offshore oil and gas exploration. And after promising fairness and open debate, Pelosi has resorted to hard-nosed parliamentary devices that effectively bar any chance for Republicans to offer policy alternatives.

“I’m trying to save the planet; I’m trying to save the planet,” she says impatiently when questioned. ‘I will not have this debate trivialized by their excuse for their failed policy’.”

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Climate Depot’s Morano response: Yea! Now can we go back to driving cars, eating meat and using appliances, and controlling our own home thermostats?!

Cheers! Take a moment to let it sink in! With the Inflation Reduction Act going into law, the long battle to fight ‘global warming’ has finally been solved! Let the good times roll! “Roll out the barrel, we’ll have a barrel of fun. Roll out the barrel, we’ve got the blues on the run. Zing boom tararrel, ring out a song of good cheer!”

BUT WAIT…The pork-barrel Inflation Reduction Act will not even impact global CO2 levels, let alone the climate!

See:Analysis: Biden’s 50% emissions reduction target for 2030 (if achieved) would have a ‘nearly unmeasurable’ impact on overall global CO2 emissions

Statistician Bjorn Lomborg: Biden’s IRA climate bill will ‘do almost nothing for the global temperature…even by end of century’ – ‘Will reduce temps by less than 1 thousandth of a degree F by the end of the century’

We have also heard these premature alleged climate-solving declarations before. See:

Flashback: 2015: World leaders hail ‘historic’ Paris climate deal as ‘major leap for mankind’ –

U.N. Secretary-General Ban Ki-moon: “History will remember this day,” Ban Ki-moon said after the pact was gaveled through to thunderous applause. “The Paris agreement on climate change is a monumental success for the planet and its people.”

Al Gore on UN Paris pact in 2015: “Years from now, our grandchildren will reflect on humanity’s moral courage to solve the climate crisis and they will look to December 12, 2015, as the day when the community of nations finally made the decision to act,” Gore said.

The Washington Post in 2015 reported on the final passage of the Paris pact: ‘Cheers echoed up and down the tent city where thousands of journalists, activists and business leaders awaited news of the deal, which was sealed during the final 48 hours of nearly non-stop talks.”

WaPo reported: President Obama, in an appearance at the White House, hailed the agreement as a “turning point for the world,” adding, “We came together around the strong agreement the world needed. Together we’ve shown what’s possible when the world stands as one.”

Secretary of State John F. Kerry said after the accord was announced: “This is a tremendous victory for all of our citizens–not for any one country or bloc, but a victory for all of the planet, and for future generations.”  “The world has come together behind an agreement that will empower us to chart a new path for our planet: a smart and responsible path, a sustainable path.”

Economist Lord Stern added: “This is a historic moment, not just for us but for our children, our grandchildren and future generations. The Paris agreement is a turning point in the world’s fight against unmanaged climate change which threatens prosperity.

Former French president, François Hollande, said: “This is a major leap for mankind.”

Fmr. British prime minister, David Cameron, also welcomed the deal, praising those involved for showing what ambition and perseverance could do. “We’ve secured our planet for many, many generations to come – and there is nothing more important than that,” he said.

French foreign minister, Laurent Fabius:  “History is coming, in fact, history is here,” he said. “On 12 December 2015, we can have a historic day, a major date to go down in the history of mankind. The date can become a message of life.”

Newsweek OPED: THE PARIS AGREEMENT WILL SAVE OUR LIVES

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September 24, 2022 at 12:07PM

SH and Tropics Keep Mild Ocean Temps August 2022


The best context for understanding decadal temperature changes comes from the world’s sea surface temperatures (SST), for several reasons:

  • The ocean covers 71% of the globe and drives average temperatures;
  • SSTs have a constant water content, (unlike air temperatures), so give a better reading of heat content variations;
  • A major El Nino was the dominant climate feature in recent years.

HadSST is generally regarded as the best of the global SST data sets, and so the temperature story here comes from that source. Previously I used HadSST3 for these reports, but Hadley Centre has made HadSST4 the priority, and v.3 will no longer be updated.  HadSST4 is the same as v.3, except that the older data from ship water intake was re-estimated to be generally lower temperatures than shown in v.3.  The effect is that v.4 has lower average anomalies for the baseline period 1961-1990, thereby showing higher current anomalies than v.3. This analysis concerns more recent time periods and depends on very similar differentials as those from v.3 despite higher absolute anomaly values in v.4.  More on what distinguishes HadSST3 and 4 from other SST products at the end. The user guide for HadSST4 is here.

The Current Context

The 2021 year end report included below showed rapid cooling in all regions.  The anomalies then continued in 2022 to remain near the mean since 2015.  This Global Cooling was also evident in the UAH Land and Ocean air temperature (Cooler Air over Land and Ocean August 2022 )

The chart below shows SST monthly anomalies as reported in HadSST4 starting in 2015 through July 2022.  A global cooling pattern is seen clearly in the Tropics since its peak in 2016, joined by NH and SH cycling downward since 2016. 

Note that higher temps in 2015 and 2016 were first of all due to a sharp rise in Tropical SST, beginning in March 2015, peaking in January 2016, and steadily declining back below its beginning level. Secondly, the Northern Hemisphere added three bumps on the shoulders of Tropical warming, with peaks in August of each year.  A fourth NH bump was lower and peaked in September 2018.  As noted above, a fifth peak in August 2019 and a sixth August 2020 exceeded the four previous upward bumps in NH. A smaller NH rise in 2021 peaked in September of that year.

 

Note that in 2015-2016 the Tropics peaked with an upward SH bump along with two summer NH spikes.  That pattern repeated in 2019-2020 with a lesser Tropics peak and SH bump, but with higher NH spikes.  Now in 2021-2022  the last two summer NH summer spikes are not joined by warming in the Tropics or in SH, which in August resulted in a Global anomaly close to the mean for this period.

A longer view of SSTs

To enlarge image open in new tab.

 

The graph above is noisy, but the density is needed to see the seasonal patterns in the oceanic fluctuations.  Previous posts focused on the rise and fall of the last El Nino starting in 2015.  This post adds a longer view, encompassing the significant 1998 El Nino and since.  The color schemes are retained for Global, Tropics, NH and SH anomalies.  Despite the longer time frame, I have kept the monthly data (rather than yearly averages) because of interesting shifts between January and July.1995 is a reasonable (ENSO neutral) starting point prior to the first El Nino.  The sharp Tropical rise peaking in 1998 is dominant in the record, starting Jan. ’97 to pull up SSTs uniformly before returning to the same level Jan. ’99.  For the next 2 years, the Tropics stayed down, and the world’s oceans held steady around 0.5C above 1961 to 1990 average.

Then comes a steady rise over two years to a lesser peak Jan. 2003, but again uniformly pulling all oceans up around 0.5C.  Something changes at this point, with more hemispheric divergence than before. Over the 4 years until Jan 2007, the Tropics go through ups and downs, NH a series of ups and SH mostly downs.  As a result the Global average fluctuates around that same 0.5C, which also turns out to be the average for the entire record since 1995.

2007 stands out with a sharp drop in temperatures so that Jan.08 matches the low in Jan. ’99, but starting from a lower high. The oceans all decline as well, until temps build peaking in 2010.

Now again a different pattern appears.  The Tropics cool sharply to Jan 11, then rise steadily for 4 years to Jan 15, at which point the most recent major El Nino takes off.  But this time in contrast to ’97-’99, the Northern Hemisphere produces peaks every summer pulling up the Global average.  In fact, these NH peaks appear every July starting in 2003, growing stronger to produce 3 massive highs in 2014, 15 and 16.  NH July 2017 was only slightly lower, and a fifth NH peak still lower in Sept. 2018.

The highest summer NH peaks came in 2019 and 2020, only this time the Tropics and SH are offsetting rather adding to the warming. (Note: these are high anomalies on top of the highest absolute temps in the NH.)  Since 2014 SH has played a moderating role, offsetting the NH warming pulses. After September 2020 temps dropped off down until February 2021, then all regions rose to bring the global anomaly above the mean since 1995  June 2021 backed down before warming again slightly in July and August 2021, then cooling slightly in September.  The present 2022 level compares with 2014 and also 2018.

What to make of all this? The patterns suggest that in addition to El Ninos in the Pacific driving the Tropic SSTs, something else is going on in the NH.  The obvious culprit is the North Atlantic, since I have seen this sort of pulsing before.  After reading some papers by David Dilley, I confirmed his observation of Atlantic pulses into the Arctic every 8 to 10 years.

But the peaks coming nearly every summer in HadSST require a different picture.  Let’s look at August, the hottest month in the North Atlantic from the Kaplan dataset.

The AMO Index is from from Kaplan SST v2, the unaltered and not detrended dataset. By definition, the data are monthly average SSTs interpolated to a 5×5 grid over the North Atlantic basically 0 to 70N. The graph shows August warming began after 1992 up to 1998, with a series of matching years since, including 2020, dropping down in 2021.  Because the N. Atlantic has partnered with the Pacific ENSO recently, let’s take a closer look at some AMO years in the last 2 decades.

 

This graph shows monthly AMO temps for some important years. The Peak years were 1998, 2010 and 2016, with the latter emphasized as the most recent. The other years show lesser warming, with 2007 emphasized as the coolest in the last 20 years. Note the red 2018 line is at the bottom of all these tracks. The heavy blue line shows that 2022 started warm, dropped to the bottom and stayed near the lower tracks, before reaching one of the highest peaks in August.

Summary

The oceans are driving the warming this century.  SSTs took a step up with the 1998 El Nino and have stayed there with help from the North Atlantic, and more recently the Pacific northern “Blob.”  The ocean surfaces are releasing a lot of energy, warming the air, but eventually will have a cooling effect.  The decline after 1937 was rapid by comparison, so one wonders: How long can the oceans keep this up? If the pattern of recent years continues, NH SST anomalies may rise slightly in coming months, but once again, ENSO which has weakened will probably determine the outcome.

Footnote: Why Rely on HadSST4

HadSST is distinguished from other SST products because HadCRU (Hadley Climatic Research Unit) does not engage in SST interpolation, i.e. infilling estimated anomalies into grid cells lacking sufficient sampling in a given month. From reading the documentation and from queries to Met Office, this is their procedure.

HadSST4 imports data from gridcells containing ocean, excluding land cells. From past records, they have calculated daily and monthly average readings for each grid cell for the period 1961 to 1990. Those temperatures form the baseline from which anomalies are calculated.

In a given month, each gridcell with sufficient sampling is averaged for the month and then the baseline value for that cell and that month is subtracted, resulting in the monthly anomaly for that cell. All cells with monthly anomalies are averaged to produce global, hemispheric and tropical anomalies for the month, based on the cells in those locations. For example, Tropics averages include ocean grid cells lying between latitudes 20N and 20S.

Gridcells lacking sufficient sampling that month are left out of the averaging, and the uncertainty from such missing data is estimated. IMO that is more reasonable than inventing data to infill. And it seems that the Global Drifter Array displayed in the top image is providing more uniform coverage of the oceans than in the past.

uss-pearl-harbor-deploys-global-drifter-buoys-in-pacific-ocean

USS Pearl Harbor deploys Global Drifter Buoys in Pacific Ocean

Footnote Rare Triple Dip La Nina Likely This Winter

Here’s Where a Rare “Triple Dip La Niña” Might Drop the Most Snow This Winter Ski Mag

The unusual weather phenomenon might result in the snowiest season in years for some parts of the country.

The long-range winter forecast could be good news for skiers living in the certain parts of the U.S. and Canada. The National Oceanic and Atmospheric Administration (NOAA) estimates that the chance of a La Niña occurring this fall and early winter is 86 percent, and the main beneficiary is expected to be mountains in the Northwest and Northern Rockies.

If NOAA’s predictions pan out, this will be the third La Niña in a row—a rare phenomenon called a “Triple Dip La Niña.” Between now and 1950, only two Triple Dips have occurred.

Smith also notes that winters on the East Coast are similarly tricky to predict during La Niña years. “In the West, you’re simply looking for above-average precipitation, which typically translates to above-average snowfall, but in the East, you have temperature to worry about as well … that adds another complication.” In other words, increased precip could lead to more rain if the temperatures aren’t cooperative.

The presence of a La Niña doesn’t always translate to higher snowfall in the North, either, as evidenced by last ski season, which saw few powder days.

However, in consecutive La Niña triplets, one winter usually involves above-average snowfall. While this historical pattern isn’t tied to any documented meteorological function, it could mean that the odds of a snowy 2022’-’23 season are higher, given the previous two La Niñas didn’t deliver the goods.

 

 

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September 24, 2022 at 11:55AM