A modelagem hidrodinâmica aplicada à redução de ... - IHO

Brazilian Navy Hydrographic Center (NHC)
Chart Datum for Rivers in Brazil
4 st Tidal and Water Level Working Group Meeting (IHO)

Brazilian Inland Waterways

1. Rivers under tidal influences

DRY SEASON: mesotides (1.5m)
(Rivers under tidal influences)
RAINY SEASON: “microtides” (0.2m)

``
Local Chart Datum = approximated MLWS
(calculated with main HC)
Secondary rivers: derived from analyses of tidal
measurements during the low river stage, over a period
of 1 month.
Estuary: over long period
(Rivers under tidal influences)

Water level information for the Navigators
Observed data : tide staff hourly readings
transmitted by local radio station
Harmonic Preview doesn’t work
(Rivers under tidal influences)
Just local companies navigate in this rivers
Forecasting models not yet implemented
It’s expected to be solved by Wavelet method

2. Rivers under non tidal influences

( Rivers under non tidal influences)
Local Chart Datum = 90th or 94th Percentile
M-3 Resolution 3/1919 ( A2.5)
In non-tidal waters, in order to allow the development of regional solutions,
it is recommended that an appropriate long term range of low/high water definitions
of the lower/upper 94-100 percentile be adopted.
Derived from analyses of water level measurements during the
low/high river stages, over a period of 10 to 30 years.

Height (cm)
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
-100
9/1/1990
9/1/1991
Solimões River _ Tabatinga Station
Monthly minimum heights (1990 – 2010 )
Chart Datum defined by 94th Percentile ( 2,10 m )
9/1/1992
9/1/1993
9/1/1994
9/1/1995
9/1/1996
9/1/1997
9/1/1998
9/1/1999
9/1/2000
9/1/2001
9/1/2002
( Rivers under non tidal influences)
9/1/2003
9/1/2004
9/1/2005
9/1/2006
9/1/2007
9/1/2008
9/1/2009

( Rivers under non tidal influences)
Water level information for the local Navigators
Observed data : “water level staff” daily readings
The dissemination of the readings is done
daily through the local radio stations
and
weekly through the Radio Warnings to Mariners
at the site of Hydrographic Center.

( Rivers under non tidal influences)
Water level information between two staffs
Forecasting models not yet implemented
Staff readings works well in Paraguay River