On the North Atlantic extreme cyclone activity

Storm cyclones in the North Atlantic

“…For example, in a number of European regions (Spain, France, Germany, and Great Britain) according to the results of studying the interrelation between cyclones and the extreme wind speed in Europe obtained in [11] and based on model computations, the trend towards increase in the number of storm cyclones with the extreme wind speed is observed for the climate warming scenario. The analysis of the variability of cyclone activity in the North Atlantic carried out by the authors of the present paper in their previous studies [2,3] demonstrates that in recent decades in the region under study the number of extremely intensive (extremely deep) cyclones has increased relative to the decrease both in the total number and in the number of moderately intensive (by the depth of development) cyclones.…”

“…How ever, the com par i son of av er age long-term val ues of the fre quency of cy clones com puted by var i ous meth ods us ing var i ous ini tial data carried out in [1] for var i ous sea sons and re gions of the globe, demonstrated that the com pu ta tions based on the NCEP/NCAR reanalysis data in the North At lan tic pro vide the higher fre quency of cy clones in sum mer as com pared with win ter. Thus, the higher val ues of the fre quency of storm cy clones in some ar eas of the North At lan tic, first of all, in the north ern ar eas of Eu rope in summer, can be caused, firstly, by the larger num ber of cy clones as com pared with win ter and, sec ondly, ac cord ing to the re sults pre sented in [3], by the higher fre quency and in ten sity of ex tremely deep cy clones in these ar eas in the sum mer half of the year. It should be noted that in winter the gen er a tion of storm cy clones with the high wind speed occurs in the ar eas of high at mo spheric baroclinity formed un der the con di tions of great tem per a ture dif fer ence be tween the ocean and at mo sphere [4,5].…”

“…4. Vari a tions of the con tri bu tion (%) of deep cy clones (with the pres sure of £970 hPa) to the to tal num ber of storm cyclones in sum mer (1,4,7) in the area of Ice lan dic low, (2,5,8) in North ern Eu rope, and (3,6,9) in the north of the Eu ro pean part of Rus sia for dif fer ent gra da tions of the max i mum wind speed: (1-3) £17 m/s, (4-6) 17-24 m/s, and (7-9) >24 m/s.…”

“…Interannual vari abil ity of the fre quency of cy clones for the gra da tions of the max i mum wind speed in(1,3,5) win ter and(2,4,6) sum mer in dif fer ent ar eas of the North At lan tic and Eu rope: (a) the Ice lan dic low, (b) North ern Eu rope, (c) the north of the Eu ro pean part of Rus sia. (1, 2)The num ber of cy clones with the wind speed of <17 m/s;(3,4) the num ber of cyclones with the wind speed from 17 to 24 m/s; (5, 6) the num ber of cy clones with the wind speed of >24 m/s.…”

“…(1, 2)The num ber of cy clones with the wind speed of <17 m/s;(3,4) the num ber of cyclones with the wind speed from 17 to 24 m/s; (5, 6) the num ber of cy clones with the wind speed of >24 m/s.…”