Tiber & PO

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The anal . of two bi-millennial ri : Tiber and Po riv r noods. Dario Camuffo' and ... {elcconnccti ns betwecn {he twO rivers and Iheir d.fferenl response tO the same.
................ ............................... ....... . ....... ...............................

... . . . . . . . . . ..... .... U ~:I::::':::.:.:.:'.:.:.: .. :-: é:m".;.: ~: ./... ,.:1600 >1600 >1600 S >1600 S > 16007

S 1700 S S 1722 S S S S 1741 S

Note

S S 1688 >1600 1895 1800 >1600 1956 1827

S 1755 S 1641

S 1711 1599

S S

1642 S 1625 1722 1617 1608 1690

S f100d wilh stagnanl waler D great damage to bui1dings - the numbers in lhc column 'Note" report the height or the f100ds in cm - no comments have been reported for lhe f100ds BC for the uncertainty derived by lhe short description and me differenl urbanization of the city.



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0.30 , - - - -- - - - - - - - - - - - - - - -- -----, 0.25 0.20

FD 0.15 0.10 0.05

-400 -200

O

200

400

600

800

1000 1200 1400 1600 1800 2000

years

Figure l:

Secular rrequency distribution (FD) of tbe Ooods or the River Tiver in Rome (afler Camurro and Enzi, 1994)

0.12 0.10 0.08

PS

0.06 0.04 0.02 0.00 lO

20

50

100

200

500

1000

years

Figure 2:

Power spectrum (PS) or the recurrence intervals (yr) or the noods or the River Tiber in Rome.




 444

in modem limes, after the dark ages between lhc 1Olhflllh centunes. In the sccond millennium. there are (wO dominant peaks. one at the beginning of the 14th centu!)' which corresponds lo Wolf Minimum on wlar aCllvlly 0282- 1342), and another

al

the tum of

lhe 15/1 th centuries. righI in the middle of the pOrcr Minullum . During tlle Maunder MIOImum however. there was a secondary maJumum, which

as oot dominanl in

comparison with other tluctuations (Camuffo and EnIJ, 1994). Th noodings of the Po. like the Tiber. were much more frequenl during Ihe second half of Ihe 151h century . The

M~

A analysis gives a highly nuctualing graph without domlnant peaks (Fig.

4) . There are arious peaks Ihal correspond to 30 yr and ilS mulllpies and lhere ìs a sharp rctum peak a litlle after 400 yr and anolher al 700 yr but nOI signilicam grcalcr Ihan Ihe Nyquist frequency thal

corre~pond

xceplional tloo