ATHENS -- The recent spate of unsettled weather in Greece is the result of atmospheric instability that is normal at the start of summer and the autumn, while there is no evidence that conclusively points to climate change as the cause, Patras University professor of atmospheric physics Athanasios Argyriou claimed in statements to the Athens-Macedonian News Agency (ANA) published on Sunday. He also predicted a high chance that both temperatures and rainfall over the summer will be higher than the average for the period 1993-2016.
"The main reason [for the current bad weather] is the instability of the atmosphere, which is intense at the start of the summer and the start of autumn. During this particular time, the increase in the intensity of solar radiation serves to heat up the surface of the Earth and the layers of the atmosphere that are close to it. The upper layers, however, remain colder. This leads to a 'forceful' rise of hot and moist air to the upper strata," he explained.
"This strong upward movement causes regions of differing electrical charge to arise, therefore the appearance of atmospheric electrical activity," he added, noting that a second consequence was to cause significantly different pressures, which led to strong winds.
A third consequence was the sudden cooling of water vapour, which at very high altitudes where temperatures remain below zero led to the formation of hail stones, he added.
Asked whether climate change might be responsible for the phenomena, Argyriou said "that there is not any evidence at this time that would indicate this." He noted that such instability is normal and occurs every year, though it varies in its duration and intensity.
"The indications we have at this time point to an increased possibility that temperature and rainfall levels, both in the summer and in the autumn, will be higher than the climate average for 1993-2016," he said.