Ana Mon ei o, Helena Madu ei a, The shape and magni ude o Po o’s hea island, 45
h
ISOCARP
Cong ess 2009
1
The shape and magni ude o Po o’s hea island as a sus ainabili y
indica o
1. In oduc ion
One o he mos o en used a gumen s o p omo e low ca bon ci ies has been he need o
adap u ban a eas o global wa ming. This is, in ou opinion, a p eca ious and uns eady
op ion because d i es us in o a complex and endless con o e sy abou he eal alue o
human ac ions on clima e beha iou a a global scale and push us away om he needed
solu ions o sol e he eal p oblems ha a ec s he quali y o he ai we b ea he and he
clima e o he place whe e we li e.
While he impo ance o human ac i i ies in he global clima e sys em is s ill unknown o su e
because clima e has a chao ic pe o mance and an imp ecise ime lag esponse, he local
ela ionships be ween human ac i i ies and he mic oclima e a e easy o demons a e and
unde s and looking, o ins ance, o he impac s in he a mosphe ic chemis y and ene gy
budge .
The e o e, he appeal o c ea e low ca bon ci ies excessi ely ancho ed in he global wa ming
h ea s can be se e e weakened and e en ail because people – ci izens and decision
make s – will, wi h some legi imacy, expec o see he e ec s o hei new a i udes and
ac ions on clima e answe s, and, hey may no come as hey expec .
So, i we wan o imp o e ou u ban ecosys ems’ sus ainabili y and a he same ime
discou age he inpu s o la ge amoun s o g eenhouse gases in he a mosphe e o a oid
some po en ial undesi able answe s om he clima e sys em, we mus y o downscale his
issue using local and egional cause-e ec ela ionships. A his scale le el, he clima e
beha iou ’ mechanics is much mo e clea and easie o e i y.
The u ban hea island migh be a good op ion o mo i a e he implemen a ion o low ca bon
ci ies because i is a s eady e idence o human in e e ence in clima e sys em. The
iden i ica ion o causes – gaseous and liquid emissions, was e, new geome ies, new
ma e ials, dec ease o g een a eas, la ge and e y ine icien ene gy consump ion, e c. – and
consequences - he mal posi i e anomalies, ain all changes, wind modi ica ion, a mosphe ic
pollu ion, e c. – is easy o do a he local and egional le el.
The shape and magni ude o u ban he mal anomalies due o u ban li es yle and planning
op ions a e indeed excellen indica o s o some o he majo ci ies’ pa hologies, namely he
huge inc ease o CO emissions.
Since Luke Howa d’s s udies o London u ban clima e, published in 1818, he e ha e been
an ex ao dina y numbe o wo ks done in u ban a eas ha exp ess clea ly how he u ban
me abolism ma e s o local clima e. One o he main key issues ackled, in some o hese
s udies, is p ecisely he ai quali y deg ada ion gene a ed by se e al human ac i i ies and by
he way a mosphe ic ci cula ion is changed because o he new a i icial geome ies o e en
by he dec ease o CO sink capaci y (less wa e su aces, g een a eas, e c.).
A Po o, we ha e al eady da a o he mal and humidi y measu emen s inside he
me opoli an a ea since 1990, and he achie ed esul s migh help o explain be e how we
need, as indi iduals and as socie y, o implemen a as shi ing owa ds a low ca bon way o
li e.
Ana Mon ei o, Helena Madu ei a, The shape and magni ude o Po o’s hea island, 45
h
ISOCARP
Cong ess 2009
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One o he mos ob ious examples o new imbalances c ea ed by man du ing he
u baniza ion p ocess may be seen in ou ci y looking o he way how i assis ed a he same
ime o a ca bon emissions inc ease due o he di e si ica ion and inc ease o human
ac i i ies and, simul aneously, o a conside able con ac ion o CO sinking capaci y because
o he g een a eas emo al. This double and cumula i e s ess upon a mosphe e is a
decision make s’ and u ban planne s’ esponsibili y because hey igno ed na u e complexi y
and ailed o ha e holis ic and sys emic app oach o he u ban ecosys em.
2. Po o case s udy
2.1. The sp ead o u ban li e s yle
All popula ion’s p ojec ions show ha human beings, despi e e e y hing, will con inue o
p e e li ing in u ban a eas han in u al ones. This will be pa icula ly e iden in less
de eloped coun ies which may mean an eno mous imbalance inc ease be ween he size
and loca ion o he a ailable space, esou ces and people needs (Fig. 1). Since 2003 ill
2030 he u ban popula ion in he wo ld is expec ed o ise om 3 billion o 5 billion while he
u al popula ion is expec ed o dec ease, in he same lag o ime, om 3.3 billion o 3.2 billion
(Fig. 1).
Fig. 1 – UNPD Popula ion p ojec ion (2007).
Since 2007, he wo ld has, o he i s ime in his o y, mo e u ban han u al inhabi an s and
acco ding o UNPD p ojec ions he annual a e will aise 1.8% wha means an expec ed
doubling in a 40 yea s pe iod.
Fo he ime being one o he majo app ehensions comes p ecisely om he way his
li es yle ha e sp ead a an ex emely high a e in de eloping coun ies whe e he g ow h o
u baniza ion s a ed in 1970 wi h a popula ion inc ease a e ha was he double o he u al.
In A ica, o ins ance, he a e o e passes he 4.5% pe yea - a doubling in an in e al o 15
yea s.
This u ban g ow h p ocess changed comple ely he social, economic and man-en i onmen
ela ionships. The complexi y and in ensi y o he e i o ial and social mul idimensional
sculp u e c ea ed by his new li es yle gene a ed an imbalance be ween people needs and
a ailable na u al esou ces ha ca ied en i ely new aces on ea h.
0
1000000
2000000
3000000
4000000
5000000
6000000
7000000
8000000
9000000
10000000
Nº ( housands)
To al popula ion To al popula ion Mo e De eloped Coun ies To al popula ion Less De eloped Coun ies
Ana Mon ei o, Helena Madu ei a, The shape and magni ude o Po o’s hea island, 45
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ISOCARP
Cong ess 2009
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2.2. Po o’s u baniza ion p ocess
Po ugal ollows he EU u ban g ow h a e end wi h conside ably highe alues (Fig. 2).
Howe e , Lisbon and Po o, he wo majo Po uguese ci ies show, as in all EU, a dec ease
in u ban g ow h a e a e he 80’s (Fig.3).
Fig.2 – UNDP u ban g ow h a e p ojec ions (2007).
Fig. 3 – Po o’s si e and geog aphical posi ion.
Fig.3 – UNDP u ban g ow h a e p ojec ions o Lisbon and Po o (2007).
Po o is he second mos impo an own in Po ugal and is si ua ed inside a me opoli an
a ea (GAMP - Po o Me opoli an A ea) wi h 1 281 424 inhabi an s, loca ed in he NW coas
o Ibe ian Peninsula (Fig. 4 and 5).
In 2005, Po o had 233 465 inhabi an s. I is a ci y wi h a daily lux o mo e han 500 000
pe sons. I concen a es mainly se ices – adminis a i e, educa ional and cul u al – and
o e s mo e han 218 000 jobs. Abou 50% o he employees come om nea by
municipali ies using public and p i a e anspo s.
Po o had an eno mous economic g ow h du ing he h ee las decades. Especially a e
becoming membe ship o he EU, in 1986, Po ugal has cons an ly bene i ed om signi ican
amoun s o EU unds in o de o c ea e and/o enew i s p oduc i e issue, in as uc u es and
human esou ces quali ica ions. Du ing his pe iod we assis , in Po o, a a conside able
0
0,5
1
1,5
2
2,5
3
3,5
1950-
1955
1955-
1960
1960-
1965
1965-
1970
1970-
1975
1975-
1980
1980-
1985
1985-
1990
1990-
1995
1995-
2000
2000-
2005
2005-
2010
2010-
2015
2015-
2020
2020-
2025
A e age annual a e(%)
Lisbon Po o
Ana Mon ei o, Helena Madu ei a, The shape and magni ude o Po o’s hea island, 45
h
ISOCARP
Cong ess 2009
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change in indus ial and comme cial loca ion pa e ns and in accessibili y ne wo ks. This was
closely ollowed by g ea changes in beha iou and men ali ies. These new economic pe iod
o hope and p ospe i y, ansla ed by an inc ease in he amily incomes, ca ied also a g ea
emp a ion o su i e in a wild compe i ion inside an enla ged and mo e appella i e ma ke ,
which un o una ely led also some negligen a i udes owa ds all he en i onmen al
componen s (eg. ai , wa e , soil, e c.).
Fig. 4 – Si e and geog aphical posi ion o Po o.
Fig. 5 - Po o Me opoli an A ea (GAMP).
Ana Mon ei o, Helena Madu ei a, The shape and magni ude o Po o’s hea island, 45
h
ISOCARP
Cong ess 2009
5
I o all his we add he ac ha hese las h ee decades has been a ime o emendous
p og ess in he scien i ic and echnological inno a ion, i is explained he belie ha i was
possible o eplica e any u ban model ega dless each geog aphical speci ici y. The
con ic ion was ha e e y hing could be sol ed wi h c ea i i y, science, echnology and ex a
inpu s o ene gy. Po o has se e al u ban planning e idences o his way o u ban planning
a ha ime.
Po o’s popula ion e olu ion was, un il he 80’s, e y simila o he hy hm o i s me opoli an
a ea (GAMP). A e his decade, while Po o’s popula ion dec eases, i s me opoli an a ea
expe ienced a popula ion inc emen (Fig. 6 o 9). The demog aphic eg ession o Po o along
he las decade o he 20 h cen u y happened mainly because o he huge housing
decen aliza ion, as well as o an eno mous all on he bi h a es.
Fig. 6 – Po o’s inhabi an s (INE, 1884-2001).
Fig. 7 – Po o popula ion densi y (INE, 2001).

Ana Mon ei o, Helena Madu ei a, The shape and magni ude o Po o’s hea island, 45
h
ISOCARP
Cong ess 2009
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Fig. 8 – Buildings cons uc ed be o e 1919 (INE, 2001)
Fig. 9 – Buildings cons uc ed a e 1996 (INE, 2001).
Po o’s popula ion d ainage p ocess, mos ly owa ds he GAMP’s nea by municipali ies, and
he bi hs d op was accompanied by s uc u al changes in amily ype and in he age py amid
dis ibu ion. The a e age amily size diminished and he numbe o single pa en amilies
augmen ed as well as he numbe o lonely elde ly people inc eased.
The CMP’s mobili y epo (2007) con i m he high exp ession o indi idual mo emen s in he
ci y o Opo o daily a ic - a o al o 93 housand a els by ca egis e ed be ween 7:30 a.m.
and 9:30 a.m (Fig. 10 o 12).
30 housand o he o als 42 housand mo o ehicles ci cula ing inside he ci y go o he
cen al u ban a ea, especially o he old own – Baixa – Boa is a oundabou and Asp ela
(CMP, 2007).
Fig. 10 – C oss-ci y a ic be ween 7.30-9.30 am (CMP, 2007, pg.7).
Ana Mon ei o, Helena Madu ei a, The shape and magni ude o Po o’s hea island, 45
h
ISOCARP
Cong ess 2009
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Fig. 11 – Ra io in-ou a ic be ween 7.30-9.30 am (CMP, 2007, pg.17).
As Madu ei a (2001) showed in he esea ch, he compa ison o g een su ace shape and
a ea be ween 1890 and 2001, clea ly exp esses he sus ainabili y o he de elopmen and
u ban planning op ions (Fig. 12).
Fig. 12 - Po o’s g een a eas in 1890 and 2000 (Madu ei a, 2001).
Ana Mon ei o, Helena Madu ei a, The shape and magni ude o Po o’s hea island, 45
h
ISOCARP
Cong ess 2009
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3. The u ban hea island in Po o (1990-2005) e sus ca bon emission and sink
capaci y es ima ions
3.1. Me hodology o de ine he u ban hea island
To e alua e he he mal anomalies inside Po o we ha e done i ine an measu emen s in a
alida ed ansec whose s a shape allow se e al poin s o da a alida ion (Fig.13).
No e
pon o de medição
0 500m
Fig.13 – Po o’s i ine an measu emen s ou ing (1990-2005).
The chosen ou e e lec s a wide ange o u ban acies – opog aphy, mo phology and
me abolism. I includes mos o he highe al i udes and lowe a eas, i comp ises places a
away om he sea and he closes ones. T ies o c oss dis ic s a e o g ea buil
compac ness and he mo e ecen esiden ial blocks wi h high and spaced housing a eas a
he same ime ha goes h ough a eas o g ea p omiscui y o use. The ou e has also
samples o di e en u ban unc ions - indus ial, comme cial and esiden ial.
The da a acquisi ion was made wi h a Del a OHM-HD 8501 digi al he mohig ome e ins alled
on he igh side o he ca oo o passenge s’ ehicle a he heigh o abou 1.5 m.
The ime lag be ween he beginning and end o he ou e – 70-80 minu es - p e en ed us
om using, di ec ly, he empe a u e alues eco ded. We s anda dized he ob ained da a
se ies calcula ing he di e ence be ween each eco d and he simul aneously eco ded alue
a he clima ological e e ence s a ion o Po o Se a do Pila .
This ou e was epea edly done unde di e en wea he condi ions, weekdays and seasons.
The e we e also done some measu emen s using he same da a acquisi ion p ocedu es
inside speci ic a eas inside Po o – Asp ela, Co doa ia, Sé – and in he nea by municipali ies
– Ma osinhos, S ª Ho a, Espinho, S.João da Madei a – ha con i m he esul s ob ained in
hese ou e (Gois, Balkes bal,)
3.1. Me hodology o de ine ca bon emission and sink capaci y
To es ima e he CO
2
emissions we used he da a compiled by he Ca bon Dioxide
In o ma ion Analysis Cen e , wi ch indica es he annual CO
2
emissions om ossil pe
coun y. The Po o CO
2
emissions om ossil- uel we e calcula ed p opo ionally o i s
popula ion a each census da e.
Ana Mon ei o, Helena Madu ei a, The shape and magni ude o Po o’s hea island, 45
h
ISOCARP
Cong ess 2009
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To es ima e he ci y sink capaci y we used de Ci yG een me hod, de eloped by he US
Fo es Se ice, which calcula es he amoun o ca bon s o ed in he ees ep esen ed on he
land co e map and calcula es he annual ca bon emo al by he ees. CITYg een de ines
h ee dis ibu ion ca ego ies based on he diame e o he ee, wi ch a e associa ed wi h a
ce ain mul iplie :
Ca bon S o age Capaci y = S udy a ea in ac es x Pe cen ee co e x Ca bon S o age Mul iplie
Ca bon Seques a ion Annual Ra e = S udy a ea in ac es x Pe cen ee co e x Ca bon Seques a ion Mul iplie
In he absence o p ecise da a on ee age dis ibu ion, we used an a e age mul iplie
3.2. Resul s
3.2.1.Shape and magni ude o he Po o’s u ban hea island
Be o e any u he commen abou he a e age noc u nal u ban hea island ound in Po o
(Fig. 14), we mus emembe ha he ci y is di ided in o wo dis inc a eas, he wes e n pa ,
lowe and plan, and he eas , wi h highe al i udes and mo e ugged. We mus also keep in
mind ha he Dou o i e side slopes a e s eep and ha i is o his a ea o he ci y ha
con e ge mos o he s ee s, wi h a NNE-SSW o ien a ion, ha go o he oldes and his o ic
ci y cen e. These old own oad ne wo ks ha e been d awn be ween g ea g ani e and all
buildings blocks ha make e y di icul he en ance o sunligh ill he lowe loo s o
buildings wha e e he exposu e.
Fig. 14 – A e age noc u nal u ban hea island a Po o (Mon ei o, 1993).
The eas a ea o he ci y co esponded o he u al ing a he beginning o he 20
h
cen u y
and, since hen, su e ed an eno mous inc ease in he occupa ion densi y. The buildings a e
usually lowe , bu in he in e io , he space is comple ely illed by “ilhas” – an answe o he
lack o housing o he lowe socio-economic classes who immig a ed o he ci y in he middle
o he 20
h
cen u y.
The wes e n a ea was occupied mos ecen ly and has a la ge numbe o new
neighbou hoods, whe e indi idual houses and / o la ge blocks o la s ha e been eme ging
o e wide a enues.