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The Metropolitan Jerusalem Master Plan
The Metropolitan Jerusalem Master Plan
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increase air humidity in the area by
20-30 percent and lower temperatures
significantly, a most important factor in
Jerusalem’s hot, dry summer climate.
The Jerusalem forest runs along the
road coming from the coastal plain. Today
this area is rich in flora and tall, full-
grown trees. The breeze flowing from the
Mediterranean brings warm air during the
day, and which is filtered and purified by
passing through the forest, which protects
Jerusalem from the west, as well as giving
the air greater humidity.
Since sand can be swept up into the hot
air and create heat wave conditions only in
very dry weather, cooling using plants and
evaporation are not only an effective and
esthetic means of acclimatization, they are
the only solutions for heat waves. In Israel,
heat waves are defined as days where
average relative humidity is less than 50%
on the coast or 45% in the mountains. A
heat wave is considered heavy if relative
humidity is lower than 20% in the
mountains or 35% on the coast.
Solutions to heat wave conditions can
be found in tree-planting. Large groupings
of big leafy trees create a protective belt in
high humidity. When hot, dusty air comes
through these trees, the moisture weighs
the sand down, sinking it to the ground.
This is a very delicate balance, and bringing
humidity levels up by even one percent
can break the dry heat. When the hot air
hits the trees, humidity can rise by 20-30%
almost immediately, breaking the dry heat.
Simulated imagery of
Golomb Street as it may
appear after it becomes
pedestrian-friendly
Sustainability in Jerusalem
main streets north-to-south and smaller
ones east-to-west – creates a framework
for construction which provides thermal
comfort for both commerce and residence.
In the future planning of Jerusalem
neighborhoods, this positive lesson should
be learned from these neighborhoods:
it is possible to plan in a manner that
contributes to the quality of life of the
residents and visitors.
Climate comfort
One of the ways in which it is possible
to preserve a pleasant climate in the
metropolitan Jerusalem region is by use of
diverse flora. Acclimatization using flora
is most economical in terms of use of
energy and natural resources.
Trees are an ideal means of creating the
shade needed in open spaces and indoors.
Today, trees are planted on the streets of
Jerusalem, but it is possible and necessary
to increase their use in future planning and
urban development. Thus, for example,
in many places there are trees planted
only on one side of the street, which of
course provides shade only on one side,
as opposed to two rows of trees with a
pedestrian walk between them – which
would offer a shaded place for walking at
all hours of the day, and such an option
should be preferred.
The most economical way to create
comfortable temperature conditions in an
open area, in terms of space, is by creating
an urban boulevard, which has four main
elements along the entirety of its length:
• Traffic lanes going in both directions.
• Accessible, comfortable, shaded parking
along the streets.
• A green lung and linear park – at least
four rows of trees along the entire
length: one row for each sidewalk and
two rows on the traffic island between
the traffic lanes.
• A central traffic island with sidewalks,
shaded with flora, for pedestrians and
cyclers.
A classic example of a street with all
four of these elements is Rothschild
Street in Tel Aviv. There is great potential
for the use of streets with several of
these elements in Jerusalem and for
incorporating missing elements in order
to make the city’s streets ideal in terms
of climate. Making these streets more
comfortable for residents and tourists
would turn them into lively urban
boulevards.
The types of trees chosen are also
of importance. Some trees are especially
effective for protecting from the sun, such
as walnut, plane, oak and Teresa trees. All
of these are tall deciduous trees, which
reach up to 15-30 meters in height. There
is also importance in planting trees that
have high evaporation levels, such as privet,
quince, yew, boxwood, cypress and sniper
trees. Use of these trees could assist in
cooling the metropolitan region by natural
evaporation. Cooling by evaporation is
suitable for especially high temperatures,
and its efficiency rises as humidity levels
drop. These are summer conditions in
metropolitan Jerusalem. Thus, planting
these types of trees on the streets of
Jerusalem could significantly lower the levels
of energy used for cooling homes.
Proper and smart use of trees can
The wind
blowing from the
Mediterranean brings
warm air during the
day, and this air is
filtered and purified
on its way through
the forest, which
protects Jerusalem
from the west
Sustainability in Jerusalem