Malta’s annual mean ambient temperature has risen by around 1.5 °C since 1952, according to a new multi-decade report. 

That is equivalent to an increase of 0.2 °C per decade. 

The study, published by the National Statistics Office on Friday, explores the island's weather trends from 1952 to 2020 and says Malta is getting warmer, drier and experiencing more extreme weather events. 

The report found that air and sea temperatures have steadily climbed over the years, while Malta has experienced less rainfall and humidity. 

Thunderstorms, droughts, and heatwaves, on the other hand, have become more common over the study period. 

The NSO report is written by Charles Galdies an associate professor at the University of Malta.

He has previously headed the MET office and served as Malta’s representative on the World Meteorological Organisation.

What did the report find?

Sunnier island

According to the report, the average sunshine duration has been climbing steadily since 1961. 

Winter months showed the sharpest rise in sunshine duration since 1961, with the highest increase seen during the month of February. 

Malta is getting warmer and drier, the study has found. Photo: Chris Sant Fournier.

This is equivalent to an increase of 0.1 hours per decade for the 60-year period. That means every 10 years, Malta gets six minutes more sunshine.  

Malta is also getting less cloudy.

The report says that the annual mean cloud cover trend shows a decrease of 0.1 oktas per decade.  

An okta is a unit of measurement used to describe the amount of cloud cover at any given location - a measurement of 0 okras means that there are absolutely clear skies.  

How climate has changed. Graphic: NSO

Air temperature climbing

The report says the air is also getting warmer. The annual mean, maximum and minimum air temperatures show a clear upward trend since 1952.

2016 saw the highest annual mean ambient air temperature (20.1 °C) since 1952, just above the value for 2001 (19.9 °C) which ranks second. 

Malta’s nights are also getting hotter. Some 80 per cent of the warmest night-time temperatures since 1952 occurred during the last 20 years.

Since 1952, Malta’s annual mean ambient temperature is about 1.5 °C higher, equivalent to an increase of 0.2 °C per decade. 

The highest maximum ambient temperature has increased by 1.2 °C since 1952, translating into a decadal increase of 0.2 °C.

Rainfall running dry

Over the past few years, Malta has been recording more dry years than in the past. A quarter of the top 20 years with the lowest annual total rainfall were recorded from 2001 onwards. 

During the last 20 years, 2016 had the least rainfall (324.8 mm) followed by 2001 (338.2 mm) and 2020 (386.9 mm). 

Between 1952 and 2020 rainfall decreased by 10.3 mm per decade.

The 24-hour rainfall rate decreased by around 0.3 mm per decade since 1952. 

The number of days with thunderstorms has increased during the period 1952-2020.

The autumn period is Malta’s most thundery season, while the month of November registered the greatest increase in thunderstorms.

Storms are getting more frequent, even if Malta is experiencing less rainfall.

Less wind

The wind speed shows a declining trend of 0.8 knots (0.4 metres per second) over the past 60 years. 

Winter has seen the steepest reduction in the overall wind speed, followed by spring, summer and autumn. 

North-westerly is the most common wind direction, followed by westerly and easterly. 

Hot water

The highest mean sea temperature was registered in August of 2003 and the same month of 2020 when a temperature of 28.0 °C was recorded. 

Some 60 per cent of the 20 maximum sea temperatures occurred during the last 20 years. 

Results show a decadal increase of 0.4 o C in the mean sea temperature of Maltese waters since 1978. 

Malta is getting less humid

A strong negative trend has occurred, equivalent to 4.7 percentage points in relative humidity for the entire period of 1961-2020. 

This is equivalent to 0.8 percentage points per decade. 

The strongest negative trends in relative humidity have been seen to occur during the warmer months (May to September). 

Some three-quarters of the years with the lowest 20 relative humidity anomalies have been registered from 2001 onwards.