Weather has an impact on everything from economic activity to energy consumption. Being able to spot potential problems or opportunities caused by our weather is really important.
Long-range forecasting can be seasonal or sub-seasonal and generally refers to any time range above 10 days. It is, as you might expect, less precise than short or medium term forecasting, but it has a vital role to play in providing insight into weather patterns for the month or season ahead.
While short-term forecasts may be used to ascertain if it's likely to freeze overnight or if it’s going to be dry at the weekend, long-range forecasts focus more on identifying trends e.g. is it likely to be a colder winter than last. This information can then be used by retailers, farmers and local authorities for example, to plan and prepare accordingly.
In this edition of the Met Éireann podcast, Post-Doctoral Researcher at Met Éireann, Dr. Laura Zubiate explains how gathering information from the whole earth system (land, sea, ice and atmosphere) is essential when producing long-range forecasts.
"There are slowly varying elements in the earth’s system such as the oceans and the cryosphere, or the ice. Those retain more information than the atmosphere. The atmosphere is more chaotic and in 10-15 days the signal is lost, but these elements retain information from the initial conditions further. That is why it is possible to forecast, not exactly the kind of weather there’s going to be 45 days from now, but next month is it going to be colder or warmer than average."
Dr. Zubiate also describes how some weather patterns and systems that occur in one part of the world, can influence weather in another part e.g. how the North Atlantic Oscillation contributed to a snowstorm in Madrid a couple of months ago, or how El Niño activity over the central Pacific results in wetter than average conditions in Florida.
Meteorologists at Met Éireann, Dr. Noel Fitzpatrick and Liz Walsh, end this month’s podcast by looking back at some of the weather events from last year that were exacerbated by our warming planet, including hurricanes in Central America and forest fires in Australia and California.
Keep up with monthly episodes of the Met Éireann podcast by subscribing at rte.ie/podcasts or wherever you get your podcasts.