For NOAA, it looks like we’re well on the way toward seeing one of the most powerful El Ninos ever recorded. And already, there’s some brutal Fall and Winter weather events starting to emerge as a result. One event, in particular, is today roaring into the US West Coast like a Godzilla-hurled freight train.
It’s just one upshot of a Monster El Nino in a record warm world. A weather and climate event — one likely pumped up by an overall atmospheric warming of 1 C above 1880s levels — that will likely continue to have severe and worsening global impacts over the coming months.
(Ocean waves hit insane heights of 43 feet [13.2 meters] today as another powerful storm roars into the US West Coast. Image source: Earth Nullschool.)
One of the 3 Strongest El Ninos On Record
NOAA’s September, October, November ONI Index, the key zone for measuring El Nino strength, hit a +2.0 degree Celsius positive anomaly this week. That’s just 0.3 C shy of the most powerful El Nino ever recorded — 1997-1998 which peaked out at +2.3 C in the same monitor. With October, November and December likely to show even hotter overall readings for the Central Equatorial Pacific, it appears that the 2015-2016 El Nino will strike very close to this ONI high mark. Peak weekly sea surface temperature values already exceeded top 1997-1998 temperature levels for NOAA (+2.8 C for 1997-1998 vs + 3.1 C for 2015-2016). So we wait on the ONI three month measure for October, November and December to give broader confirmation.
The other major El Nino monitor — the Bureau of Meteorology (BOM) in Australia — has weekly sea surface temperatures peaking at +2.5 C in the same zone. This is 0.2 C short of peak 1997-1998 values. BOM notes that the current El Nino is near peak and that, according to its own measures, is unlikely to exceed 1997-1998 but will likely hit within the top 3 strongest events. According to BOM:
The 2015–16 El Niño is strong, and likely to rank in the top three events of the past 50 years. Presently, several key indicators fall short of their 1997–98 and 1982–83 values, both in the ocean (e.g. sub-surface temperatures, which have peaked around +8 °C this year, compared to +12 °C in 1997–98), and atmosphere (e.g. SOI, for which monthly values peaked around −20, while 1982–83 had several months at −30).
(NOAA Equatorial Pacific sea surface temperature [SST] anomaly tracking appears to indicate that the 2015-2016 El Nino may have hit peak during mid November. Though a second peak is possible in December, atmospheric and ocean trends will tend to push for gradual SST cooling over the coming months. Overall, the 2015 to 2016 El Nino is likely to be among the top 3 strongest on record. A climate event that in a world warmed by 1 C above 1880s values has the potential to set off some very extreme weather over the coming months. Image source: NOAA SST Anoms 5N to 5S.)
Based on a reading of these two analysis by expert agencies, we revise our previous statements to come into line with NOAA and BOM forecasting. Though it’s still possible that 2015-2016 may exceed peak 1997-1998 intensity, it is more likely that the current El Nino will fall into the range of the top three most intense such events. This is likely due to the fact that El Nino has probably already peaked and that though some indicators show 2015 as exceeding 1997-1998 in intensity (NOAA weekly SST values), the broader, long-term indicators still rank 1997-1998 as the most intense in the modern record.
Potentially Very Severe Weather on The Way
That’s not to say that related weather events won’t be quite extreme. In some respects, hottest ever atmospheric and ocean temperatures on a global basis provide even more available energy for storms, heavy rainfall, droughts, and wildfires. Globally, the Earth has warmed by between 0.2 and 0.3 C from peak 1997-1998 atmospheric temperature values to those we are likely to experience during 2015 and 2016. That means rates of evaporation and precipitation have increased by about 2 percent overall. In addition, new climate instabilities have tended to arise due to increased rates of glacial melt, polar amplification (especially in the Northern Hemisphere), and related ocean surface warming along with the weakening of some of the major oceanic heat conveying currents.
A top 3 strongest El Nino firing off in this global climate environment is, therefore, not entirely the same creature as a Monster El Nino firing off during the 1980s or even the 1997-1998 El Nino. In particular, the added atmospheric moisture loading, the slowing down of the Gulf Stream off the US East Coast and related back-up of warm water in that region, and the added rates of evaporation due to overall warming of the Earth-Ocean system present potentially more severe drought hazards for regions like Brazil and Australia, potentially more severe extreme storm hazards for the US West Coast as the storm track ramps up, and potentially more severe Winter oceanic and coastal storm hazards for the US East Coast, the North Atlantic and the United Kingdom.
Disaster Officials Worry, Make Calls For Readiness
Federal disaster officials are keenly aware of these risks and have been issuing warnings for regions of the US West Coast since October. NOAA and FEMA bulletins have urged people to keep extra food and water on hand and to prepare for extended periods of sheltering in place during heavy rainfall, landslide, snowfall or coastal flooding events. Statements today continue to urge preparedness for what is likely to be a very extreme Winter weather season. In San Jose Mercury News, FEMA emergency manager Bob Fenton expressed his extreme concern today after a disaster preparedness drill in Sacramento:
“It is critical that citizens take the risk seriously. If you hear a warning to evacuate, act accordingly. People often want to ‘wait and see’ — but, please, don’t wait. Everything can be replaced, but your life can’t.”
The US Southwest and South-Central California are especially vulnerable to severe flooding events during strong El Ninos in the December, January, February timeframe. Such events can deliver powerful rivers of tropical moisture to this region. Called Pineapple Express, these atmospheric rivers can develop along an arc running from the Equator, through Hawaii and then terminating over the US Southwest. The most extreme of these events have the potential to deliver 200, 500, or 1000 year deluges resulting in many feet of rainfall for the Central Valley region. A situation that some researchers have called an Ark-Storm and have linked to the (likely El Nino-related) Great Flood of 1862.
In today’s context, we have one of the top 3 strongest El Ninos firing off in an atmosphere that, due to human forced warming in the range of 1 C, sees an overall 7-8 percent increase in the rate of evaporation (vs 1880s contexts) and precipitation. So any river of moisture that does develop may likewise become further engorged than was previously typical, thus resulting in more severe rain storms and a related heightened flood risk. It’s a risk, that in any case, FEMA disaster managers are taking very seriously.
43 Foot Waves off US West Coast
As officials issued warnings and FEMA managers drilled in Southern California, another powerful storm packing 60-80 mile per hour winds, heavy rains, and 43+ foot waves roared into the US West Coast this week. The 960 mb storm kicked off coastal flood, gale and storm warnings from Northern California through Washington State.
(Another powerful storm roars into the US West Coast bringing with it flooding rains, heavy surf, coastal storm surges, and mountain snows. The currently very strong El Nino is likely deliver more severe storms of this kind over the coming months. Image source: NOAA GOES.)
Interior flood warnings were also issued as between 4 and 18 inches of rain fell over the past 3 days with 2-4 inches more expected today. The event had already spurred over 9 landslides even as, according to the Weather Channel, more than two dozen river gauges had topped flood stage across Washington and Oregon. It’s a heavy soaking that began in November and just keeps getting worse with each new storm.
These storms are fueled by a powerful flood of heat and moisture boiling off the Godzilla El Nino in the Pacific. A dynamic that’s generating an extraordinarily powerful Pacific storm tack. This week, models predict another extreme storm — one that is expected to bomb out as a 930 mb monster packing 75 kt winds and 52+ foot waves in the Bering Sea between Russia and Alaska. And given the way El Nino is charging up the atmosphere, these Pacific beasts are bound to keep roaring on in.
Links:
Climate Prediction Center — Cold and Warm Episodes by Season
Monster 2015 El Nino May Be Most Intense Ever Seen
Pacific Northwest Storm Parade to Bring Rain, Wind and Snow
Federal Officials Warn Californians to Prepare for Onslaught
NOAA Ocean Prediction Center — Pacific
Hat tip to DT Lange
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