Air temperature changes until now

Data for North Cyprus for the period 1975–2021 show the highest warming rate for mean minimum air temperatures followed by the mean air temperatures and lastly the mean maximum air temperatures. Warming rate for mean minimum temperature, 0.61 °C per decade, is one of the fastest warming trends reported in the literature. The warming trends in this period for mean temperature and mean maximum temperature are 0.38 and 0.28 °C per decade, respectively (14).

Observations from the beginning of the 20th century show an increasing trend in the annual mean temperature in Cyprus, with a rate of increase of 0.01°C per year. Overall, a warming of approximately 1‐1.58°C has been observed over the 20th century. This increase exceeds the global value observed for the same period. The rates of change of precipitation and temperature are greater during the second half of the 20th century. Most of the warm years in the 20th century were recorded in the last 20 years (4).

During the 20th century the minimum daily temperatures have generally increased at a larger rate than the maximum daily temperatures, resulting in a decrease in the long‐term diurnal temperature range (4).

Heat waves

Studies have shown that in the eastern Mediterranean, the intensity, length and number of heat waves have increased by a factor of six to eight since the 1960s (11). Not all studies confirm these results of increasing trends, however. Heat wave characteristics have been assessed for a number of stations in the eastern Mediterranean (including three in Turkey and one in Cyprus) and the Middle East for the period 1973−2010 (12). In this study a heat wave is defined as a period where daily maximum temperature exceeds the 95th percentile of the time series of daily maximum temperature data for the summer season (here taken from the first of June to the first of November). The results showed that the number of heat waves increased during 1973−2010 at all stations. On the other hand, the maximum temperature during these heat waves did not change, implying no change in heat wave intensity. Furthermore, no significant trends in the heat wave duration are observed (12).

Precipitation changes until now

Mean annual precipitation decreased during the last century by 1mm/year on average. This decrease was larger during the second half compared to that in the first half of the 20thcentury as a result of the higher frequency of occurrence of low precipitation and drought years. Average annual precipitation was 559 mm in the first 30‐year period of the 20th century and 462mm in the last 30‐year period, which corresponds to a decrease of 17% (4).

Air temperature changes in the 21st century

For the Mediterranean islands Cyprus, Sicily and Crete, projected changes in daily maximum and daily minimum temperatures have been calculated for the period 2031-2060 compared with 1971-2000. This was done for a moderate (RCP4.5) and high-end (RCP8.5) scenario of climate change. The calculations are based on five regional climate models (RCMs) (13). For Cyprus the projected increase of maximum temperatures is 1.6-1.7 °C in all seasons. Under the high-end scenario of climate change, the projected increase of maximum temperatures is higher than 2 °C for all seasons. Daily minimum temperatures are projected to increase more than 1.2 °C for all three islands for both scenarios of climate change.

For Cyprus, a temperature rise is projected for the 2021–2050 period of 1.3-1.9 ⁰C with respect to 1961–1990, depending on the season. For the 2071–2100 simulation the projected temperature rise is 3.6-5 ⁰C (1). Similar results were reported from other studies for this area (2,3).

According to a mid-line scenario of climate change there will be 25 more “heatwave” days per year (temperatures exceeding 35⁰C) in 2021–2050 with respect to 1961–1990, while the 2071–2100 simulation shows an increase of about 2 months (1).

In 2026-2050 the number of summer days is projected to be 2 weeks/year longer, and the number of tropical nights 1 month/year longer (2,8).

Eastern Mediterranean and the Middle East (EMME)

For the Eastern Mediterranean and the Middle East an analysis was carried out of long-term meteorological datasets (period 1901-2006) along with regional climate model projections for the 21st century (SRES scenario A1B) (5). The results suggest a continual, gradual and relatively strong warming of the area of about 1-3°C in the near-future (2010–2039), to 3–5°C in the mid-century period (2040–2069) and 3.5–7°C by the end of the century (2070–2099). Daytime maximum temperatures appear to increase most rapidly in the northern part of the region, i.e. the Balkan Peninsula and Turkey. Maximum day time temperature increases more strongly than mean night time minimum temperature (9).

Extremely high summer temperatures are projected to become the norm by 2070–2099; the coolest summers at the end-of-century may be warmer than the hottest ones in the recent past. As an example, the hottest summer on record in Athens in 2007 would be among the 5% coolest ones by the end of the century (5,9). The relatively strong upward trend in the northern parts of the Eastern Mediterranean and the Middle East indicates a continuation of the increasing intensity and duration of heat waves observed in this region since 1960 (6). According to regional climate model results based on the IPCC SRES scenarios A1B, A2 and B2, the number of heat wave days, here defined as days with maximum temperatures exceeding the local 90th percentile of the reference period (1961–1990), typically increases by a factor of 4–10 by the middle and 7–15 by the end of the century, with the strongest increases in the Middle East (9).

Current and future daytime mean temperature trends in the Eastern Mediterranean and the Middle East typically vary from 0.28° to 0.46°C per decade. The largest increases appear in some continental locations such as Belgrade, Sofia, Ankara, Baghdad and Riyadh with trends in excess of 0.4°C/decade. The same analysis was performed for daytime maximum and night-time minimum temperature; for daytime maximum temperature the largest upward trends are calculated for Belgrade, Sofia, Tirana and Ankara with 0.48°, 0.46°, 0.45° and 0.44°C per decade, respectively. For night-time minimum temperature, large positive trends exceeding 0.40°C/decade are derived for Belgrade, Riyadh, Baghdad, Athens, Sofia and Ankara (5,9).

A1B scenario results suggest that by the end of the century, the frequency of very hot days (maximum day time temperature >35°C) may increase up to 1–2 weeks per year in mountainous parts of the northern EMME and by about a month in much of the rest of the region. The frequency of ‘‘tropical’’ nights (mean night time minimum temperature > 25°C) also increases strongly, by nearly a month per year in the Balkans and coastal areas, and more than two months in the Gulf region, exacerbating the daytime heat stress. By the end of the century in most cities, the coolest summers may be warmer than the hottest ones today (9).

Precipitation changes in the 21st century

For the 2021–2050 simulation the decrease of precipitation varies from 6% to 18% depending on the area of the island, while for the 2071–2100 simulations this decrease varies from 20% to 35%, compared to 1961–1990 (1). Similar results were reported from other studies for this area (2,3). It has been stressed though that the ability of climate models to estimate changes in future precipitation in this area is limited (8). Projected changes of daily precipitation for the period 2031-2060 compared with 1971-2000, based on five regional climate models, do not show clear changes of precipitation or precipitation extremes for Cyprus under a moderate (RCP4.5) and high-end (RCMs) scenario of climate change (13).

In winter, precipitation decreases more than the average total rainfall (about 25% for the 2021–2050 simulation, and about 40% for the 2071–2100 simulation). This higher decrease in winter, is accompanied, only for the 2021–2050 period, by an increase of precipitation in autumn (about 35%). The simulated increase in autumn precipitation may be due to elevated sea surface temperatures in the region after the hot summer period together with enhanced sea breezes (1). Along with a decrease in the amounts of seasonal rain an increase in the number of extreme rainfall events is projected. The intervals between dry and wet spells are also expected to increase (3).

Furthermore, in both simulations an increase of the dry period with precipitation below 1mm is indicated. More specifically for the 2021–2050 simulation this increase is about 7% (15 more days), and 12-25% for the 2071–2100 period (1).

Eastern Mediterranean and the Middle East

From the analysis of long-term meteorological datasets (period 1901-2006) along with regional climate model projections for the 21st century (SRES scenario A1B) a decline of annual precipitation is projected of 5–25% in 2040–2069 and 5–30% in 2070–2099 relative to the reference period 1961–1990 (5). The decreases will be particularly large (>15%) in Cyprus, Greece, Israel, Jordan, Lebanon, the Palestine territories and Syria. As a result of precipitation decrease, and also due to population growth rates, the per capita available internal water resources may decline strongly, for example by 50% or more by mid-century in Cyprus (10).

In the Balkans, Turkey, Cyprus, Lebanon and Israel, the number of rainy days may decrease, e.g. by 5–15 days at mid-century and by 10–20 days per year at the end-of-century (5). This appears to be a continuation of a trend observed in Greece since about 1960 (7).

The intensity of precipitation (maximum amount of rain per day) is expected to decrease except over the northern Balkans and the Caucasus (5).

References

The references below are cited in full in a separate map 'References'. Please click here if you are looking for the full references for Cyprus.

1. Giannakopoulos et al. (2010)
2. Hadjinicolaou et al. (2010), in: Shoukri and Zachariadis (2012)
3. Israel's Second National Communication on Climate Change (2010), in: Shoukri and Zachariadis (2012)
4. Shoukri and Zachariadis (2012)
5. Lelieveld et al. (2012)
6. Kuglitsch et al. (2010), in: Lelieveld et al. (2012)
7. Nastos and Zerefos 2009, in: Lelieveld et al. (2012)
8. Hadjinicolaou et al. (2011)
9. Lelieveld et al. (2013)
10. Chenoweth et al. (2011), in: Lelieveld et al. (2013)
11. Kuglitsch et al. (2010), in: Coumou and Rahmstorf (2012)
12. Tanarhte et al. (2015)
13. Varotsos et al. (2021)
14. Bey et al. (2024)