Tweedledee and Tweedledum; ’97 and ’15

This just in from someone else, Nate M1:

When sea surface temperature (SST) anomalies from the Great Niño of 1997-98 are compared in June 15, 1997 with the one now developing on June 15, 2015 the differences are nil.

That’s it.  Hope you like it.

The one in 1997-98 was a “Comprehensive Niño”, that is, it included sea surface temperatures that were much above average  in both the Classic Niño locale,  just off the coasts of Peru and Columbia, and extended all the way to, and included,  the “New Niño” locale, the one way out there in the Pacific along and a little north and south of  the Equator (called “Region 3.4” by real scientists2).   That 97-98 one was gigantic; earth shaking; the one in progress also appears like a gigantic one, too, so far, to add fudge words.

Take a look for yourself, first June 15, 2015, and below,  June 15, 1997.

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Not only was it extraordinarily wet in the Southwest that water year,  especially  in central and southern California (LA had over 30 inches, and mountain stations over 70), but the Great Niño of 1997-98 was also associated with a leap upward of the earth’s temperature.  So, be wary of a jump in the earth’s temp during the next year or so.  Catalina is  already be experiencing a temperature jump; 109 F here yesterday.  Egad.

Let’s hope, too,  that this Niño is more like the other “recent” Great Niño, 1982-83 rather than the one in 97-98.  In the former one, Catalina received more than 32 inches of rain during that water year,  October 1, 1982 through September 30, 1983.  In 1997-98, we “only” received 24 inches (about 7 inches above average our ~17 inch average here in Catalina).  Old timers still talk about how the washes flowed all year in 82-831.  Recharge those aquifers!

Ninos strengthen the southern portions of the jet stream by increasing the temperature difference between the Tropics and the mid-latitudes, so that low pressure systems are larger and stronger in the middle and lower latitudes of the eastern Pacific (see Bjerknes and “company”, 1960s).  Typically, the  low pressure centers that accumulate in the Gulf of Alaska are less vigorous, their strength sapped by the shift of the stronger winds aloft toward the south.

Huge plumes of cloud arise over these warmer than average waters from masses of Cumulonimbus clouds where the trade winds of the southern and northern hemisphere are colliding.  Those vertical fountains of moisture eject clouds out of the tropics and of middle and high clouds that  get caught up in the stronger cool season troughs that come by, enhancing their rain and snow output, and leading to a much cloudier overall cool season.  Recall that Biosphere 2 largely failed due to the excessive cloud cover of the 92-93 winter in southern Arizona associated with a Niño.

BTW, It only takes a few degrees of ocean surface warming for clouds to transition from an area of passing light showers with little accumulation, showers that falls from modest Cumulus clouds or clumps of Stratocumulus,  to giant, recurring clusters of Cumulonimbus clouds.  When cloud bases are warmer, the amount of water being condensed is greatly increased, and that in turn, allows the clouds to be warmer inside, more buoyant,  than cloud are when they form over those normally very cool eastern Pacific equatorial waters.

Unfortunately, a lot of wildlife down around the Equator in the eastern Pacific, such as around the normally semi-arid Galapagos Islands and other islands to the west,  is severely disrupted by the sudden onset of frequent, heavy tropical rains.  The same is true for the coasts of Peru and Columbia where normally very dry areas are awash in water.  Fishing gets crappy, too.


HOWEVER, note in the plot for 2015 how much the larger the area of  above average SSTs in the Gulf and eastern Pacific are compared with 1997.  Hmmmm.   Not sure how that will play into current Great Niño.  It would be prudent to contain our excitement to some extent since weather NEVER exactly repeats itself.  Don’t start gathering animals and building an ark just yet.

So, am a little worked up about 2015-2016 water year, as I am sure you are, too.  Thanks Nate, I think.

In the immediate future, how will all that excess warm water affect our upcoming summer rain season?

I don’t know.  Clueless, really, as are the people who actually study the summer rain season in detail.  Could go either way, dry or wet. Lot of uncertainty about how a good Niño affects Arizona weather in the summer.

But we might well have “better”, stronger tropical storm remnants affect us in the fall, maybe like last September and October when what turned out to be a dud Niño was in formation and those wamer waters combined with extra warm waters off the immediate Baja and California coasts (this latter phenomenon now deemed the “California Niño”), that helped sustain tropical storms as they drifted northward.

Once again, ending with a lot of ? and the Mysterians….”96 Raindrops”; “…too many raindrops for one heart.”

The End


1Nate M., formerly of the University of Washington’s Climate Impact Group, now at NOAA’s Southwest Fisheries Center, Monterrey, CA.  Nate and I used to have “punting wars” right there in the middle of Husky Stadium.  Oh, yeah.

2Its the region between 120 W and 170 W longitudes, 5 N and 5 S latitudes), and in the area in between.  HOWEVER, in the plots above, note that the longitude has been incremented upward from the Dateline of 180 W, and continues to increase so that 120 W longitude is 240 degrees W longitude.  This is not something that Cloud Maven Person did for humor, like claiming that the Equator goes through Hawaii, as he sometimes does to see if anybody notices the error, is reading his blog.  Hasn’t been caught yet.

3Heck, add a few more days to that 82-83 water year from Oct ’83, so that the above total would include the rains from Tropical Remnant (TR) Octave, and you’d have a Seattle-like 36 inches of rain here in Catalina!  Unbelievable.