#Snowpack news February 12, 2024
Day: February 12, 2024
February 2024 #ENSO Outlook: All along the #LaNiƱa WATCH-tower — NOAA
Click the link to read the article on the NOAA website (Tom Di Liberto):
February 8, 2024
On a brisk early February morning, all of us El NiƱo-Southern Oscillation (ENSO) forecasters emerged from our burrows and saw our shadows. That can mean only one thing: conditions are favorable for the development of La NiƱa within the next six months. Yes, theĀ February ENSO OutlookĀ officially announces that we are in aĀ La NiƱa Watch, even while, at the current moment, the Pacific Ocean remains in an El NiƱo (this is simultaneous to the ongoing El NiƱo Advisoryāhere isĀ an explainerĀ to help sort it out). The outlook gives a 79% chance that El NiƱo will transition to ENSO-Neutral by the AprilāJune period, and then a 55% chance the Pacific transitions into La NiƱa in JuneāAugust. Confused? Iāll explain it all without the help of any prognosticating rodents (take THAT, Punxsutawney Phil).
El NiƱoās current status
Letās start with the here and now. At the current moment, El NiƱo remains across the equatorial Pacific Ocean. In January, sea surface temperatures remained above average across most of the Pacific, though temperatures fell a bit across the eastern and central Pacific. Monthly values in the NiƱo-3.4 region (the key tropical Pacific monitoring region for ENSO and the basis for the Oceanic NiƱo Index (see below) dropped from just over 2Ā°C above average in December 2023 to 1.87Ā°C above average in January 2024. Overall, the most recentĀ Oceanic NiƱo Index (ONI) valueāhow NOAA classifies the strength of eventsāfor NovemberāJanuary places this eventās peak strength at ~2Ā°C, or the fifth highest on records back to 1950 (**).
Atmospherically, El NiƱo weakened a bit as well over the last month. Remember, El NiƱo is an ocean-atmospheric phenomenon. During El NiƱo, the atmosphere over the tropicsāthe Walker Circulationāgets all jumbled up. The result in the Pacific is weakened trade winds, an increase in thunderstorm activity near the Dateline, and a reduction in thunderstorms across the Western Pacific (also, usually, across the Amazon). However, in January, the trade winds were closer to average across the equatorial Pacific, and while thunderstorm activity remained a bit elevated near the Dateline, it was instead closer to average across Indonesia in the western Pacific.
Put together, it looks clear that this El NiƱo event is past its peak. However, itās important to remember that El NiƱoās impacts on global temperature and precipitation can linger through April.
Is that all?
While everything I said above is all fine for the surface, the BIG story is happening underneath the sea surface in the Pacific. Averaged across the entire equatorial Pacific Ocean, ocean temperatures in the upper 300 meters returned to near-average for the first time in almost a year. And itās clear that cooler-than-average ocean waters are widespread at depth and expanding eastward, even while above-average temperatures persist closer to the surface in the central/eastern Pacific.
Where is this all going?
Thatās the million-dollar question. The seasonal prediction models that forecasters look to for guidance are pretty confident in a transition from El NiƱo to ENSO-neutral sometime during the northern hemisphere spring 2024. Following that, there is a general consensus among the models that La NiƱa will follow during the summer. Now when it comes to transitions, there is always a bit of uncertainty on the exact timing, as an El NiƱo can end in a hurry. After all, the current outlook has only a two-season difference between the end of El NiƱo (79% chance in April-June), and the start of La NiƱa (55% chance in June-August). And some of the influencers of that transition can be atmospheric patterns that are not forecastable this early on, like theĀ Madden-Julian OscillationĀ or random weather events.
How common are transitions from El NiƱo to La NiƱa?
Going back to 1950, over half of the El NiƱo events were followed shortly thereafter by a transition to La NiƱa (after a brief period of time in ENSO-Neutral). So, it would not be at all uncommon to see this sort of potential outcome this year.
Breaking that down even more by looking at similar strong El NiƱos, five of the eight events since 1950 were followed by a La NiƱa. And that transition happened rapidly. Two years (1973 and 1998) had only one 3-month period of ENSO-Neutral conditions before switching to La NiƱa. Two years (1983, 2010) had two 3-month periods of ENSO-Neutral in between. And 2015 had three 3-month periods.
Suffice to say, the historical record suggests that if the equatorial Pacific moves from a strong El NiƱo into a La NiƱa, it doesnāt seem to waste its time.
Weāll keep our eyes on the Pacific for you to help narrow down when and how this El NiƱo will end. So check back with us next month!
Signed,
The most accurate mammalian weather/climate forecasters
** A pesky annoyance is the fact the 1965-66 El NiƱo also peaked at 2.0Ā°C, but it did so only during the September-November and October-December seasons.Ā By November 1965-January 1966, it was 1.7Ā°C.Ā So, if we rank just by November-January seasons, then the current 2023-24 event is ranked fifth. But if we rank by all near-winter seasons, then this event is basically tied for fifth.Ā
The World Is Losing Migratory Species at Alarming Rates — Inside #Climate News #ActOnClimate
Click the link to read the article on the Inside Climate News website (Katie Surma):
A first of its kind U.N. study by conservation scientists finds nearly half of internationally protected migratory species are on their way to extinction.
Humans are driving migratory animalsāsea turtles, chimpanzees, lions and penguins, among dozens of other speciesātowards extinction, according to the most comprehensive assessment of migratory species ever carried out.
The State of the Worldās Migratory Species, a first of its kind report compiled by conservation scientists under the auspices of the U.N. Environment Programmeās World Conservation Monitoring Centre, found population decline, a precursor to extinction, in nearly half of the roughly 1,200 species listed under the Convention on Migratory Species (CMS), a 1979 treaty aimed at conserving species that move across international borders.
The reportās findings dovetail with those of another authoritative U.N. assessment, the 2019Ā Global Assessment Report on Biodiversity and Ecosystem Services, that found around 1 million of Earthās 8 million species are at risk of extinction due to human activity. Since the 1970s, global biodiversity, the variation of life on Earth, has declined by a whopping 70 percent.
Scientists and economists use complicated models to try to predict how fast the world can transition away from fossil fuels. The Washington Post analyzed 1,200 modeled pathways for the world to shift to clean energy and found that only four of them showed the world hitting the 1.5C target without substantially overshooting or using speculative technology (like large-scale carbon capture) that doesnāt yet exist. At this point, many experts believe that the economy is too stuck on fossil fuels to transition fast enough for 1.5 degrees.
Does that mean weāll pass catastrophic tipping points?
Thatās a more difficult question. Scientists donāt know exactly when certain tipping points ā like theĀ collapse of the Greenland ice sheetĀ or the release of greenhouse gases from thawing permafrost ā will occur. Itās very hard to predict and model these types of catastrophic changes.
And 1.5C isnāt a magic threshold; itās not as though as soon as we pass that number, Antarctic ice sheets will collapse and ocean circulations will grind to a halt. But one thing is certain: For every tenth of a degree of warming, tipping points are more likely. Two degrees is worse than 1.9 degrees, which is worse than 1.8 degrees, and so on.
And at each tenth of a degree, the infrastructure and systems that the world has built ā electric grids, homes, livelihoods ā will become more strained. Our modern world simply was not designed for temperatures this high. At some level, the final temperature of the planet isnāt what matters most. Itās where countries can actually get carbon emissions to zero ā and stop contributing to future warming altogether.
Earth breached a feared level of warming over the past year. Are we doomed? The world still hasn’t missed its #climate goal — The Washington Post #ActOnClimate
Click the link to read the article on The Washington Post website (Shannon Osaka). Here’s an excerpt:
Itās official: For the past 12 months, the Earth wasĀ 1.5 degrees Celsius higherĀ than in preindustrial times, scientists said Thursday [February 8, 2024], crossing a critical barrier into temperatures never experienced by human civilizations. According to the European Unionās Copernicus Climate Change Service, the past 12 months clocked in at a scorching 1.52 degrees Celsius (2.74 degrees Fahrenheit) higher on average compared with between 1850 and 1900. At some level, thatās not surprising ā the past 12 months have been scorching, as a warmĀ El NiƱo cycleĀ combined with the signal ofĀ human-caused warmingĀ generated heat waves and extreme weather events around the globe.
āThis El Nino maximum is riding on top of a base climate that is continuously warming due to climate change,ā Andrew Dessler, a climate scientist at Texas A&M University, said in an email. āThe combination of them is whatās giving us such hot global temperatures.ā
But does this mean that the worldās most famous climate goal is out of reach? Not … exactly. Hereās what you need to know:
In the 2016 Paris climate agreement, almost 200 nations agreed to keep the global average temperature from exceeding 2 degrees Celsius (3.6 degrees Fahrenheit) above preindustrial levels ā and to āpursue effortsā to keep it below 1.5 degrees Celsius. The latter addition largely came from pressure from small-island states, who are at risk of disappearing under rising seas if temperatures get much higher. Scientists have shown that holding the temperature riseĀ to 1.5C could mean the survival of coral reefs, the preservation of Arctic sea ice and less deadly heat waves…
Does this mean we have missed the 1.5C climate goal? No. Thereās actually someĀ disagreementĀ about what exactly counts as breaching that threshold ā but scientists and policymakers agree that it has to be a multiyear average, not a single 12-month period. Scientists estimate that without dramatic emissions reductions, that will happen sometime in theĀ 2030s. But there could be other single years or 12-month periods that cross the line before then.
Can we still avoid passing 1.5C? Most scientists say passing 1.5C is inevitable. āThe 1.5-degree limit is deader than a doornail,ā Columbia University climate scientist James Hansen said in a call with reporters late last year.