Nandu News Reporter Cheng Kun On January 18, the Shenzhen Meteorological Bureau issued the "2021 Shenzhen Climate Bulletin" (hereinafter referred to as the "Communiqué"). The Communiqué conducted a comprehensive analysis and assessment of the meteorological monitoring information of Shenzhen in 2021 (including the Shenzhen-Shantou Special Cooperation Zone) and released the top ten weather and climate events in Shenzhen in 2021.
Nandu reporter learned from the "Communiqué" that in 2021, under the background of the influence of "double La Niña" and the continuous strong subtropical high pressure, Shenzhen's climate showed the characteristics of "the highest average temperature in history, heavy drought in stages, strong precipitation in the flood season after the weak water of dragon boats, two consecutive attacks in the early stage and late autumn", and the city's meteorological disasters did not cause casualties, and the overall climate was a general climate year.
Top 10 weather and climate events in Shenzhen
First, the average temperature is the highest in history
In 2021, the average temperature in Shenzhen was 24.0 °C, which was tied with the historical highest in 2019. The average temperature in spring (March to May) was 2.2 °C higher than usual (Figure 2), and the average temperature in March and May was 2.8 °C and 2.5 °C higher than usual, respectively, which set a new record in history; on March 25, it reached the summer standard, setting a new record for the earliest summer entry in history
Shenzhen has meteorological records since the average temperature of spring (March-May) (°C)
Second, the stage of drought is heavy
The annual precipitation is 1822.5 mm, which is slightly less than the usual year (1935.8 mm), but the precipitation stage is less serious, from November 2020 to May 2021, Shenzhen precipitation is 207.7 mm, the second lowest since meteorological records, resulting in the sustained development of meteorological drought, Shenzhen drought is the heaviest after 2004/2005; the degree of drought in Shenzhen is the heaviest after 1962/1963.
Three. Dragon boat water" is weak
During the "Dragon Boat Water" period, the average rainfall in Shenzhen was 173.2 mm, which was significantly less than the same period in the past five years (406.0 mm), and the maximum daily rainfall was 100.7 mm, and the maximum one-hour rainfall was 77.7 mm, both of which were the smallest in the same period in the past decade. In late June, the precipitation was unusually concentrated, and the average rainfall in the city was 205.6 mm, exceeding the "dragon boat water" and 2.7 times more than the same period in the past five years.
4. Heavy precipitation occurs frequently from the second half of July to the beginning of August
From the second half of July to the beginning of August, under the background of strong monsoons, Shenzhen's precipitation was unusually frequent, during which there were 18 days of precipitation above local heavy rainfall, 8 days of precipitation above local heavy rainfall, 5 days of heavy rain in the city, and 16 days of recorded extreme precipitation in short terms, all of which set the highest record since 2008 (Figure 3).
From July 16 to August 10, 2011, the number of days of local heavy rain and above, local heavy rainstorms and above precipitation days in Shenzhen, and the number of short-term extreme precipitation days (unit: days)
Five. Chapaka" process has the heaviest rainfall in the province
Typhoon Chapaka No. 2107 made landfall at 21:50 in Jiangcheng District, Yangjiang City, at 21:50 a.m. near the center of the wind (33 m/s, typhoon level). During the impact of "Chapaka", Shenzhen experienced heavy localized heavy rainstorms for three consecutive days (July 19-21), with the maximum process rainfall of 410.5 mm, the largest in the province.
Six. Lion Rock" caused continuous heavy rainstorms
Typhoon Lionrock (tropical storm level) made landfall along the coast of Qionghai City, Hainan Province, around 22:50 on October 8, with maximum wind strength of 8 (20 m/s, tropical storm level) near the center. "Lion Rock" caused Shenzhen to have two consecutive days of heavy rainstorms in shenzhen on the 8th and 9th, of which the 8th local heavy rain, the maximum 24-hour rainfall of 362.9 mm, refreshing the October extreme, the impact of rainfall since 2008 is second only to "Ayyuni" (Figure 4).
Distribution map of the city's cumulative rainfall during the "Lion Rock" period (October 8-10) (unit: mm)
Seven. Compass" gales affected the heaviest in October in nearly a decade
Typhoon Kompasu (typhoon level) made landfall along the coast of Qionghai City, Hainan Province, around 15:40 on October 13, with a maximum wind force of 12 (33 m/s, typhoon level) near the center. During the "compass" impact period, the largest gusts in Shenzhen were 13, and the gusts above magnitude 8 and 10 lasted for 50 and 15 hours respectively, becoming the typhoon with the heaviest impact on Shenzhen's gales in October in the past decade.
August continued to be hot for a record period
In September, the "autumn tiger" was heavy, with an average temperature of 29.0 °C, which was tied with the historical highest in 2017; the number of hot days of 33 °C or above was 18 days, setting a new record; and the maximum heat lasted for 9 days, the second longest in the same period in September.
IX. October suddenly turns cool into early autumn
The early october continued to be hot, the national day holiday (October 1-7) average temperature of 29.0 °C, the second highest in the same period of history, the weather gradually cooled after the national day holiday, October 22 by the strong cold air influence temperature plummeted, reaching the climate into autumn standards, the earliest autumn since 1998.
Ten. At the end of the year, strong cold air struck
In early early and late January, the climate was affected by strong cold air to reach the winter standard (January 8), the second longest (seven days) cold weather process since 2010, and the annual minimum temperature was recorded at 5.3 °C. From December 26 to 27, it was affected by strong cold air, and the minimum temperature in the second half of the year was recorded at 7.6 °C.
Looking forward to 2022, relevant experts of the Shenzhen Meteorological Bureau said that in the context of "double La Niña", it is expected that the weather and climate in Shenzhen in 2022 will show the characteristics of "continuous drought in winter and spring, late flooding, drought and flood after flooding, phased concentration of heavy precipitation, early and heavy typhoon impact, and more high temperature weather in midsummer".