Perturbation may 2010. | ||
Tidal waves #19 and #20 come detached possibly because of sustained sun wind speed. | ||
Perturbation may 2010. | ||
.1 | In the lagoon of Venice, two tide waves were late, possibly because of the conditions of the sun wind. | |
The position of the Moon. | ||
.2 | 192010-05-04u0400: the passage of the Moon above the local meridian took place, being its declination south 21°02 (spatiole for the tide wind 19). | |
Graph of the solar wind speed. |
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The tide wave in Venice (punta Salute). | ||
Legend of the tidal wave graphs. | ||
On the numbers of the tidal waves. |
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Wave 19 | High water times | difference | water level |
Forecasts (astronomical). | 2010-05-04 u 1500 | min. = | 43 |
Forecasts A+M | 2010-05-04 u 1350 | min. +70 | 60 |
As recorded | 2010-05-04 u 1500 | 69 | |
Interval 19-20 | Low water times | ||
Forecasts (astronomical). | 2010-05-04 u 1750 | min. +190 | 34 |
Forecasts A+M | 2010-05-04 u 1750 | min. +190 | 45 |
As recorded | 2010-05-04 u 2100 | 36 | |
Onde 20 | High water times | ||
Forecasts (astronomical). | 2010-05-04 u 2250 | min. +120 | 49 |
Forecasts A+M | 2010-05-04 u 2315 | min. +95 | 70 |
As recorded | 2010-05-05 u 0050 | 44 | |
Interval 20-21 | Low water times | ||
Forecasts (astronomical). | 2010-05-05 u 0655 | min. -55 | -9 |
Forecasts A+M | 2010-05-05 u 0655 | min. -55 | 5 |
As recorded | 2010-05-05 u 0600 | 21 |
Forecasts A+M. | ||
.4 | From the forecasts A+M - those where both the astronomical situation and the weather conditions are taken into account - the water levels would have been much higher, throughout. This part of the forecasts proved correct, except for the troughs of two intervals, 19-20 and 20-21. | |
.5 | The forecasts A+M were also for an earlier arrival of wave 19; this part of the forecasts proved incorrect. | |
Late arrivals for the waves 19 and 20. | ||
.6 | Compared with the forecasts A+M, the perturbation would have caused the wave 19 to be 70 minutes late, and the wave 20 to be at least 95 minutes. | |
The norm. | ||
.7 | Compared with the simple astronomical forecasts - those where the perturbations of all kinds are not taken into account - the odd number wave #19, generated late, and the even number wave #20, generated early, had to become one wave. | |
.8 | Instead, because of the Sun perturbation, both waves were late: the wave 19 was about 60 minutes late, while the wave 20 was about 100 minutes late, with regard to the normal times. | |
The two waves 19 and 20 come detached. | ||
.9 | Consequently, as an exception, the two waves, 19 and 20, did not arrive as fused into one single wave. Compared with the norm, they detached themselves by 40 minutes. | |
.10 | Between the waves 19 and 20, the interval gets accentuated: the water level gets reduced, compared with the meteo and astronomical forecasts. That's because of the delay of the wave 20. | |
.11 | By contrast, and because of the same reason, during the interval 20-21, the water level gets increased. | |
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