609
1 INTRODUCTION
As well know the climate change affect the human
activity, the agriculture and the industry as well as
thetourismbusiness(Pezzolietal.2013a).Howevera
lessbibliographywasdevelopedonthe effect of the
climate change on the maritime navigation. In fact,
alsoifsomestudies
were conductedaboutthe effect
oftheclimatechangeonthewindconditionsandthe
wave action, thestudies about themanagement and
the policies are focused principally about the
mitigation of the greenhouse gas emissions (GHG)
generatebythenavigation(Pezzolietal.2013a).
Nevertheless it is evident an
inadequate
bibliographyabouttheeffectoftheclimatechangeon
the maritime navigation. For this reason a less
literatureispresentaboutthemanagementpolicythat
the Government and the Organizations responsible
fortheportcontrolcanapplytosustaintheshipping
businessduetotheclimatechangeeffects.
There is
the awareness that conditions of
bathymetry,tides,winds,currentsandwavesfornext
decades shall have climate changes impacts on
maritimenavigation. Theriskisunderstood,butonly
in a qualitative way, as composed by Hazard,
ExposureandVulnerability(Pezzolietal.2013a).
Impact of climate changes on the Santos Harbor, São
Paulo State (Brazil)
P.Alfredini&E.Arasaki
PolytechnicSchoolofSaoPauloUniversity,SaoPaulo,SaoPauloState,Brazil
A.Pezzoli
PolytechnicofTorino,EngineeringFaculty,DepartmentofEnvironment,LandandInfrastructureEngineering,Torino,
Italy
C.P.Fournier
Baird&AssociatesCoastalEngineersLtd.,Santiago,Chile
ABSTRACT: Santos Harbor Area (SHA) in Sao Paulo Coastline (Brazil) is the most important marine cargo
transferterminalintheSouthernHemisphere.Alongtermrelativetidallevelvariabilityassessmentshowsa
consistentresponsetorelativesealevelrise.Awavedatabase
WaveWatchIIIwascomparedwithalongterm
wavedata‐basegeneratedbytheERA40‐ECMWF(2003),both localvalidated.Thecurrentbed level of SHA
OuterChannelis‐15.00m(ChartDatumor,inabbreviation,CD),maintainedbydredging.Accordingtothe
cargo throughput forecast, in 2025, the
Access Channel will have to be deepened to level of‐17.00 m. The
feasibilityofthatchoiceisdiscussedfromatechnical,economicalandconceptualnavigationpointofviewin
thatcontext.AdatasetfoundfromascalemodelofthewholeareaofSantosBay,Estuaryandnearbybeaches,
showedtheimpactofmaritimeclimatechangesuponthecoastalarea.Inthepreviousresearchesdevelopedby
theauthors,itwasdemonstratedthatthewaveclimate,thetidesandtidalcurrentsaffectharborandcoastal
structures maintenance, beaches stability, tidal inlet, sediment transport, saline intrusion and wetlands.
Consideringtheincreasing
oftheseahazardsandthehighvaluesoftheinfrastructuresinthatcoastline,itis
necessarytomitigatetherisks.Hence,basedontheresultsobtainedbytheauthors,arehighlightedguidelines
strategiessuggestedforAccessChannelsdimensions,wharvesfree‐board,jettiesdimensions,dredgingrates,
rigidandflexiblelittoraldefenses
andlandprotectionagainstflooding(includingwetlands).
http://www.transnav.eu
the International Journal
on Marine Navigation
and Safety of Sea Transportation
Volume 7
Number 4
December 2013
DOI:10.12716/1001.07.04.17
610
Astudyof136maritimecitieswithover1million
of inhabitants showed that large populations are
already exposed to coastal flooding in ports areas,
withapproximately40millionpeopleexposedtoa1
in100‐yearcoastal flood event (Nicholls et al. 2008).
Otherstudy(Beckeretal.2012)
identifiedthatclimate
change will disproportionately affect ports and port
basedeconomies.
Forharbors,themostimportantchangeislikelyto
besealevelrisebutothersfactors,includingchanges
to precipitation (both yearly averages and heavy
extreme weather events), will lead to a variety of
impacts. In fact the
climate changes generate storm
surges, inundations and coastal flooding as well as
theincreasingofcoastalhardening,coastalrunoffand
siltation requiring more frequent dredging on the
harborsthatitgeneratestheincreasedgreenhousegas
emissions(Nursey‐Brayetal.2012).
TheSãoPauloState(Brazil)Coastline(Fig.1)has
around
450km.SantosHarboristhemostimportant
in the Southern Hemisphere and the first in Latin
America. In the last decade important oil and gas
reserveswerediscoveredintheSantosOffshoreBasin
andSãoPauloCoastlinereceivedagreatdemandfor
supplier boats harbors for the petroleum industry
(Arasaki et al. 2011). Santos Metropolitan Urban
Region is one of the most important of Brazilian
Coastline,alsoconsideringthetourism.Forthatgreat
economicgrowthscenarioitisveryimportanttohave
well known the main maritime hydrodynamics
forcing processes including climate changes in tidal
levels, currents and waves, considering
the sea
extremeeventshazardsinfluenceinvesseloperations,
coastal erosion, land flooding and estuarine
mangrove wetlands survival as marine ecosystem
(Alfredinietal.2012).
The understanding of these aspects can avoid
damages and potential impacts on coastal areas,
minimizing future costs, making decisions in
mitigation and adaptation and also
show the most
dangerousandcostlyimpacts(Neumannetal.2010).
AccordingtoOsthorstandManz(2012),Pezzoliet
al(2013b)developedanin‐depthstudyaboutthejoint
effectofrainandtidesonthecoastalareawerefound
that the “coastal locations are supposed to be
particularly vulnerable to
effects of climate change.
As a consequence of the high concentration of
infrastructures and sensitive values, potential losses
due to destructive weather events are also very
significant.”
The goal of this paper is to overcome the
contraposition that it emerges between the defense
against the hydraulic risk and the management
to
preserve the environmental protection for nautical
purposes.Moreover,basingontheresultsobtainedby
theauthorsinthepreviouspublishedresearches,the
highlighted guidelines strategies are suggested for
access channels dimensions, wharves free‐board,
jetties and breakwaters dimensions, dredging rates,
rigid and flexible littoral defenses, saline intrusion
and land protection
against flooding (including
wetlands).
Figure1.Sitelocation
611
2 MATERIALANDMETHODS
The IPCC and PIANC recommendations (Pezzoli
et al. 2013a), about the study of the impact on the
climate change on the maritime navigation, are to
focusonthemetoceanvariablessuchaswind,waves,
sealevelandice.
Althoughlarge‐scaleclimaticprocessesaredriven
bytheocean‐atmosphereexchange system,very few
studies are availableon maritime impacts compared
tocontinentalimpactsduetoshorterdataseriesand
fewerhumanconsequences (Pezzoli etal. 2013a and
Pezzolietal.2013b).
Someanalysisabouttheincreasingofthesealevel
was conducted by Bindoff et
al. (2007). The authors
indicates that the global mean sea level increased at
anaveragerateofabout1.7±0.5mm/yearduringthe
twentiethcenturyandthat theratehas beenslightly
higherovertheperiod1961to2003.
In other the climate model prediction elaborated
bytheIPCCpanel
(Pezzolietal.2013a)showsthatthe
global average rate of rise over the Twenty First
centurywillbe25 mm/year,implyingthatmean sea
levelwillbe0.2÷0.5mhigherinthe2100than2000.
In the same time the waves conditions could be
affected by climate
changes in a number of aspect.
Threnberth et al. (2007) reports a statistically
significant trend of increasing annual mean and
wintermeansignificantwaveheight(Hs)forthemid‐
latitudinalNorthAtlanticandNorthPacific,western
subtropical South Atlantic, eastern equatorial Indian
Ocean, and the East China and South China Seas.
They,also,reportstatisticallysignificantdecreasesin
HsforwesternPacifictropics,theTasmanSeaandthe
southIndianOcean.Similartrendsarefoundforthe
99%extremeHswithamaximumincreaseofwinter
extremeHsof0.4mperdecadeintheNorthAtlantic.
The worsening of wave
conditions in the north‐
eastern North Atlantic is most likely connected to a
northward displacement of the storm tracks, with
decreasing wave heights in the southern North
Atlantic.
Following these indications, Pezzoli et al (2013a)
showedhowtheregionalanalysisofthesealeveland
thewaveclimatebecomeimportantas
demonstrated
by Debernard and Roed (2008) and by Sterl et al.
(2009).
Considering the lack of bibliography and
researches developed in this topic in the South
Atlanticandinpa rticularalongthecoastallineofthe
South of the Brazil, it was activated in 2010 a joint
project called “Rede
Litoral”
(http://www.redelitoral.ita.br/).
The Research Unit, based in the São Paulo
University – Polytechnic School, has the goal of the
researchfocusedonthestudyofwaveandtidallevel
analysis, maritime climate change, navigation’s
strategyandimpactonthecoastaldefensesalongthe
SãoPauloCoastlineHarborAreas(Brazil).
As well
indicated in the Introduction, this paper
summarizes the research developed by the Research
UnitoftheSãoPauloUniversity(Alfredinietal.2012,
Alfredini et al. 2013, Arasaki et al. 2011,
COASTLAB082008,Dovetta2012,Pezzolietal.2013a
and Pezzoli et al. 2013b) concentrating on the
managementpolicies.
This
study was developed analyzing three
different aspects of the problems (sea level, wave
climate and sediments transport), apparently distant
from each other, but, in fact, coordinated as well
showsbythePIANC(Pezzolietal.2013a).
The long term tidal level variability (high tide,
meansealevelandlowtide)assessment
considering
the Santos Dock Company (CDS) tidal variability
(Highest High Water or HHW, Mean Sea Level or
MSLandLowestLowWaterorLLW)forthelastsix
decades, comprising three moon nodal cycles (58
years), shows a consistentresponse of relative sea
level rise. Those figures were of similar
magnitude
thantheotherlongterm tidal seriesrecordedinSão
PauloCoastline,atthetidalgaugesofCananeia(1955
‐ 1992), according to Franco et al. (2007), 200 km
southward, and at Ubatuba (1954 – 2003), 200 km
northward(seeFig.1).
Alongtermwavedata‐base(1957‐2002)
wasmade
byacomparisonbetweenwave’sdatamodeledbythe
Europeandeepwaterdatabasemeteorologicalmodel
ERA‐40 Project (2003) and measured wave’s data in
theyears1982‐1984byacoastalbuoyinSantoslittoral
(São Paulo State, Brazil). Calibration coefficients
accordingtoangularsectorsofwave’sdirection
were
obtained by the comparison of the instrument data
with the modeled ones, and applied to the original
scenarios. Validation checking procedures with
instrumentalmeasurementsofstormsurgesmadein
other years than 1982‐1984 shows high level