Weather/Climate Events

Current climate change research is focused on what has happened in the past and what is projected to happen in the future. The study of the past relies on retrieval and analysis of temperature proxies, collection and “adjustment” of data and observations of event frequency and intensity. The projections of the potential future are based on climate models, fed with estimates of climate sensitivity, forcings and feedbacks and “tweaked” to approximate the measured past. The accuracy of the information obtained from proxies is limited. The accuracy of “adjusted” measurements is questionable. The climate models are being progressively falsified by observations. The state of the “settled science” is relatively unsettled.

While the focus of climate change research has been on anthropogenic climate change, climate continues to change as the result of natural variation as well, as it did prior to anthropogenic influences. It is not currently possible to isolate the anthropogenic change from the natural variation. The causes of the natural variation are not well understood; and, therefore, the ability to predict future natural variation is extremely limited.

The earth has fluctuated between glacial and interglacial periods. The factors which result in the initiation and termination of these periods are not well understood, since our knowledge of the transitions is based on proxies.

Within the Holocene (current) interglacial, there have been multiple fluctuations such as the Roman Warm Period, the Medieval Warm Period and the Little Ice Age. Again, the factors which result in the initiation and termination of these fluctuations are not well understood, since our knowledge of them is again based on proxies. There remain questions regarding the geographical extent of these fluctuations, though recent studies continue to suggest that they were global in extent. There also remain questions about the potential future occurrence of such fluctuations, their timing and duration.

There are numerous other weather and climate phenomena which we have been able to observe and study, but which again are not clearly understood and are not being aggressively studied. For example, we have observed that the sun passes through sunspot cycles, each of approximately 11-year duration; and, that successive cycles are of progressively decreasing strength, until they revert to higher strength for reasons that we do not understand. The Maunder Minimum coincided with the Little Ice Age. The sunspot cycle is now approaching another minimum, though its depth is still uncertain.

Another example of climate phenomena we observe but do not understand are the major ocean currents and cycles: Thermohaline Circulation (the Global Conveyor Belt), the Pacific Decadal Oscillation; the Atlantic Multidecadal Oscillation; the Indian Ocean Oscillation; and, the El Nino Southern Oscillation. The Pacific, Atlantic and Indian Ocean oscillations are climate events, in that their oscillation periods are greater than 30 years. However, the causes of individual oscillations are uncertain, as is their duration. We do not know whether there are significant variations in the strength of the oscillations over some cycle.

The ENSO oscillation is a weather event because of its much shorter, multi-year period. The strength of ENSO events varies considerably, as does the timing between events. We have experienced very strong Super El Ninos in 1997 and 2016, with numerous lesser events in the interim, not always accompanied by subsequent La Nina events of similar strength.

Most recently, we have observed an event in the North Pacific Ocean commonly referred to as the “Blob”. The first observed “Blob” occurred during the winter of 2013/2014. There is currently another “Blob’ forming for the winter of 2019/2020. It is too early to tell how the strength and duration of this new “Blob” will compare with the previous event.

In summary, there is a lot we do not currently know or understand about significant global weather and climate events, which drastically limits our ability to predict their future occurrence and the potential impacts of those occurrences.

There is much more climate science to be done before the “science is settled”.