What kind of summer will it be in the Mediterranean? Climate change interview

The increasingly warm Mediterranean Sea generates unpredictable extreme phenomena that cause alarms and risks for sea-goers especially in the summer season. We “interviewed” climate change with the help of meteorological expert Riccardo Ravagnan of Meteomed. Here’s what to do and what to do about it

Climate change interview

How well do we know the Mediterranean Climate today?
Improved technology, more extensive research, and the development of advanced climate models provide us with vast knowledge about the Mediterranean, including its historical climate variability, many complex variables are now being studied.

With what tools do we measure climate variations?
The accuracy and frequency of measurements from weather stations, satellites, rain gauges is continuously improving. Tide gauge stations then measure water temperature, salinity, sea height, ocean acidification, and monitor marine ecosystems. Because of this, we have meteorological data significant in the Mediterranean for over a century, from which we can study climate dynamics and fluctuations.

We can say with certainty that the climate is changing, on what time scale?
Today, climate change must be considered a certainty. The Mediterranean is experiencing faster temperature increases than the rest of the globe, so much so that it is considered a ‘hot spot’ of climate change.

• Find real-time marine weather forecasts here

There is much talk about the rise in the average temperature of the Mediterranean seas. What impact does variation have on extreme weather phenomena?
ISPRA (Istituto Superiore per la Protezione and Environmental Research) showed an increase in average Mediterranean temperature of +0.17°C per decade. This thermal increase, however small it may appear, has impacts on climate and weather systems, including intensification of marine heat waves and impacts on ecosystems. Warmer waters provide additional energy for disturbances and thunderstorm phenomena, including the occurrence of large hailstorms. Research published in MDPI(www.mdpi.com/2072-4292/14/17/4320) indicates that the average number of hail events increased significantly, with a more pronounced increase, even above 30 percent in the period 2010-2021 compared to the period 1999-2010, particularly in southern Italy and the Balkans.

Climate change – The extreme weather phenomena

Recent years have seen an increasing number of intense, unusual weather phenomena due to climatic variations? Or of greater intensity?
‘Extreme’ events are part of what we should begin to consider normalcy. The increased energy available between the atmosphere and the sea leads to new phenomena with different power from the recent past.

The derecho that hit Corsica and Elba, the mini-tsunami from stom-surge that swept over Portofino and Marina di Pisa, the great storm surges that destroyed the port of Rapallo, the medicanes, tornadoes, and supercells that unleash powerful hail and lightning…. Will we have more and more extreme phenomena?
The marine heat wave had a crucial factor on the August 2022 derecho, according to a recent study. The rare and severe convective wind storm that developed over the western Mediterranean Sea was substantially amplified by the extreme marine heat wave. This is something to consider since continued warming could also lead to stronger derecho in the future. We can in the same way expect to see not so much an increase in frequency in the number of Mediterranean medicanes or cyclones, but an increase in stronger cases as occurred in Libya.

In Liguria, the Caligo (advection fog) phenomenon appears every year now, and creates significant problems for boaters who in the middle of a sunny day are surrounded by fog. Is it related to the climate? How to predict it?
Caligo is a common type of fog along the coasts; it occurs when warm air flies over colder waters. can actually create significant problems for navigation. Climate change could affect its frequency and intensity, but through the use of satellites and weather webcams, we can predict its arrival.

• Find real-time marine weather forecasts here

Will we have more intense winds and higher waves in the Mediterranean?
Rising global and sea temperatures have the potential to change weather patterns, which, in turn, affect wave formation and intensity. Climate change is also affecting motion conditions in the Mediterranean area. There is a clear upward trend in both the intensity and frequency of extreme wind events in specific areas, such as the Gulf of Lion. Research in the field suggests that global warming could change wind patterns, leading to an accentuation of phenomena such as the Mistral in the western Mediterranean and the Sirocco.

How to protect ourselves – The forecast

WeatherMar bulletins on VHF, or MeteoFaxes, GRIBs, for the boater, are obsolete tools compared to weather APPs?
The more emblazoned instruments are not obsolete or inaccurate in an absolute sense but more general and less focused in the local dynamics that can have an important influence in today’s weather phenomena.
Summer storm phenomena that create serious hazards to navigation can also be predicted in the forecast phase through the use of models, which can be consulted without connection from GRIBs. However, nowcasting, a very short-term forecast that is based on actually observed radar and satellite data, is essential for these events. There is a category of thunderstorms, the MCS (Mesoscale Convective System) capable of producing wind gusts of up to 100 km/h and significantly altering wave motion; such phenomena are often sudden. Conditions that often escape classic forecasts, which is why nowcast integrations are very useful if not essential.

Professional Apps and platforms today allow for faster, more intuitive reading with better spatial resolution that provide the boater with better tools from this point of view so that he or she does not find himself or herself in difficult situations.

Regarding tornadoes (waterspouts), famous NOAA alerts are known in the United States that interrupt radio and television communications to inform citizens. Where do we stand in Europe?
There is no agency in Europe that performs exactly the same role as NOAA, which has the ability to interrupt transmissions to issue emergency warnings. However, there are initiatives that seek to fill this gap at the European and regional levels, ESTOFEX is a nonprofit organization Very useful and detailed. Alerts for intense weather events are the responsibility of the national and regional weather services, which issue forecasts, warnings and marine weather bulletins.

Are there specific indicators of interest to boaters that are often underestimated?
Basically, there is a poor weather culture among boaters that is not compensated for by the short weather courses associated with boating licenses or lectures at boat clubs. In addition to basic knowledge of the main atmospheric movements (high and low pressures), it would be useful to understand the process to follow to make sure you have a good weather forecast with you and how to check its accuracy at sea.

First we should learn to use the barometer and ‘georeference’ to the surface pressure map, which, unlike the map, makes us understand how the main centers of action will move around us. The importance of professional meteorological support lies not only in forecast quality but in the ability to receive consultation and training on the subject. Making the checklist your own in a process leading to a weather forecast allows you to ensure safety and comfort in navigation.

What a summer it will be… Are there really seasonal forecasts?
Seasonal forecasts can give us a rough indication of the likelihood of a possible large-scale scenario. They seek to identify climate trends on time scales of months, offering general projections of how anomalies in temperature, precipitation, and other climate elements might behave in a given season. But they have many limitations on smaller scales such as a Mediterranean area especially when trying to predict specific events such as extreme thunderstorms.

There is long-term damage on boaters’ boats due to climate change,
As increased UV wear or decreased antifouling effectiveness?
UV radiation remains the same, it is not affected by climate change unless emissions go into the Ozone layer, but the exact opposite is happening, fortunately. The increased amount of CO2 in the atmosphere is responsible for the acidification of the seas, but with negligible pH change in relation to material effects. The presence of algae is related to solar radiation and the presence of nutrients such as nitrogen and phosphorus. Temperatures higher than seawater, however, can promote algal blooms.

• Find real-time marine weather forecasts here