RealClimate logo


Technical Note: Sorry for any recent performance issues. We are working on it.

El Niño or Bust

Filed under: — mike @ 8 May 2014

Guest commentary from Michelle L’Heureux, NOAA Climate Prediction Center

Much media attention has been directed at the possibility of an El Niño brewing this year. Many outlets have drawn comparison with the 1997-98 super El Niño. So, what are the odds that El Niño will occur? And if it does, how strong will it be?

To track El Niño, meteorologists at the NOAA/NWS Climate Prediction Center (CPC) release weekly and monthly updates on the status of the El Niño-Southern Oscillation (ENSO). The International Research Institute (IRI) for Climate and Society partner with us on the monthly ENSO release and are also collaborators on a brand new “ENSO blog” which is part of www.climate.gov (co-sponsored by the NOAA Climate Programs Office).

Blogging ENSO is a first for operational ENSO forecasters, and we hope that it gives us another way to both inform and interact with our users on ENSO predictions and impacts. In addition, we will collaborate with other scientists to profile interesting ENSO research and delve into the societal dimensions of ENSO.

As far back as November 2013, the CPC and the IRI have predicted an elevated chance of El Niño (relative to historical chance or climatology) based on a combination of model predictions and general trends over the tropical Pacific Ocean. Once the chance of El Niño reached 50% in March 2014, an El Niño Watch was issued to alert the public that conditions are more favorable for the development of El Niño.
Current forecasts for the Nino-3.4 SST index (as of 5 May 2014) from the NCEP Climate Forecast System version 2 model.
Current forecasts for the Nino-3.4 SST index (as of 5 May 2014) from the NCEP Climate Forecast System version 2 model

More recently, on May 8th, the CPC/IRI ENSO team increased the chance that El Niño will develop, with a peak probability of ~80% during the late fall/early winter of this year. El Nino onset is currently favored sometime in the early summer (May-June-July). At this point, the team remains non-committal on the possible strength of El Niño preferring to watch the system for at least another month or more before trying to infer the intensity. But, could we get a super strong event? The range of possibilities implied by some models allude to such an outcome, but at this point the uncertainty is just too high. While subsurface heat content levels are well above average (March was the highest for that month since 1979 and April was the second highest), ENSO prediction relies on many other variables and factors. We also remain in the spring prediction barrier, which is a more uncertain time to be making ENSO predictions.

Could El Niño predictions fizzle? Yes, there is roughly a 2 in 10 chance at this point that this could happen. It happened in 2012 when an El Nino Watch was issued, chances became as high as 75% and El Niño never formed. Such is the nature of seasonal climate forecasting when there is enough forecast uncertainty that “busts” can and do occur. In fact, more strictly, if the forecast probabilities are “reliable,” an event with an 80% chance of occurring should only occur 80% of the time over a long historical record. Therefore, 20% of the time the event must NOT occur (click here for a description of verification techniques).

While folks might prefer total certainty in our forecasts, we live in an uncertain world. El Niño is most likely to occur this year, so please stay attentive to the various updates linked above and please visit our brand new ENSO blog.

If You See Something, Say Something

Filed under: — mike @ 17 January 2014

Gavin provided a thoughtful commentary about the role of scientists as advocates in his RealClimate piece a few weeks ago.

I have weighed in with my own views on the matter in my op-ed today in this Sunday’s New York Times. And, as with Gavin, my own views have been greatly influenced and shaped by our sadly departed friend and colleague, Stephen Schneider. Those who were familiar with Steve will recognize his spirit and legacy in my commentary. A few excerpts are provided below:

More »

A Bit More Sensitive…

Filed under: — mike @ 2 January 2014

by Michael E. Mann and Gavin Schmidt

This time last year we gave an overview of what different methods of assessing climate sensitivity were giving in the most recent analyses. We discussed the three general methods that can be used:

The first is to focus on a time in the past when the climate was different and in quasi-equilibrium, and estimate the relationship between the relevant forcings and temperature response (paleo-constraints). The second is to find a metric in the present day climate that we think is coupled to the sensitivity and for which we have some empirical data (climatological constraints). Finally, there are constraints based on changes in forcing and response over the recent past (transient constraints).

All three constraints need to be reconciled to get a robust idea what the sensitivity really is.

A new paper using the second ‘climatological’ approach by Steve Sherwood and colleagues was just published in Nature and like Fasullo and Trenberth (2012) (discussed here) suggests that models with an equilibrium climate sensitivity (ECS) of less than 3ºC do much worse at fitting the observations than other models.

More »

References

  1. S.C. Sherwood, S. Bony, and J. Dufresne, "Spread in model climate sensitivity traced to atmospheric convective mixing", Nature, vol. 505, pp. 37-42, 2014. http://dx.doi.org/10.1038/nature12829
  2. J.T. Fasullo, and K.E. Trenberth, "A Less Cloudy Future: The Role of Subtropical Subsidence in Climate Sensitivity", Science, vol. 338, pp. 792-794, 2012. http://dx.doi.org/10.1126/science.1227465

Cows, Carbon and the Anthropocene: Commentary on Savory TED Video

Filed under: — mike @ 4 November 2013

Guest post by Jason West and David Briske

Allan Savory delivered a highly publicized talk at a “Technology, Entertainment, Design (TED)” conference in February of this year (2013) entitled “How to fight desertification and reverse climate change.” Here we address one of the most dramatic claims made – that a specialized grazing method alone can reverse the current trajectory of increasing atmospheric CO2 and climate change.

The talk was attended by many conferees and has since been viewed on the TED website over 1.6 million times. It has received substantial acclaim in social media, some of which is available at the Savory Institute website, but it has also received considerable criticism (of particular note is a blog post from Adam Merberg and an article in Slate magazine. Although these criticism quickly followed Mr. Savory’s presentation and are broadly supported by the available science, his sweeping claims have continued to resonate with lay audiences. An apparent example is his invitation to deliver a speech to Swiss Re during their 150 year anniversary celebration in London in September, in which he is quoted as saying “…only now due largely to my TED talk on the desertification aspect of the global problem, was the public becoming aware of such hope in a world so short on solutions…”.
More »

Language Intelligence – Lessons on persuasion from Jesus, Shakespeare, Lincoln, and Lady Gaga: A Review

Filed under: — mike @ 20 August 2012

Any book that manages to link together the lessons of the Bible, Shakespeare, Abraham Lincoln, and Lady Gaga (not to mention Martin Luther King, Winston Churchill, Bob Dylan, and Jerry Seinfeld), can’t be all bad. With Joe Romm’s new book Language Intelligence, it is, in fact, ALL good. There are lessons galore for the scientists among us who value public outreach and communication. The book is a de facto field guide for recognizing and assimilating many of the key tools of persuasive language and speech, something that is ever more important to science communicators who face the daunting challenge of having to communicate technical and nuanced material to an audience largely unfamiliar with the lexicon of science, sometimes agnostic or even unreceptive to its message, and—in the case of contentious areas like climate change and evolution—already subject to a concerted campaign to misinform and confuse them.
More »


Switch to our mobile site