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T
HE NEED FOR
acquisition, analysis, data banking, and
dissemination of meteorological and hydrological data
and information to the stakeholders in the Kingdom of
Saudi Arabia, particularly the agricultural and pastoral commu-
nities, is critical in order for its citizens to continue to live
within traditional cultural activities in the marginal arid envi-
ronment of the region. The Kingdom’s efforts to provide this
type of data has displayed significant improvements in the
delivery of data and information. However, more local,
regional, and international cooperation in this arena would
enhance the delivery of these critical information requirements.
The importance of climate to the traditional cultures of the
Kingdom should be looked at from geological and historical
perspectives. In discussing the relevant meteorological agency
in the Kingdom, we will explore some past efforts in these
arenas, and illustrate some relevant ongoing projects that will
address the need for timely and urgent meteorological and
hydrological data requirements.
Geological view
The geological and climatological histories of Saudi Arabia
reflect global influences in these processes. The geological
history is linked to global tectonic frameworks including the
rift processes in the Red Sea, whereas the climatic history
reflects external and internal climatic processes over the entire
globe. Located along the Tropic of Cancer, a key climatic gradi-
ent, the Arabian peninsula is sensitive to changes in climate
the world over (and even to external influences such as solar
insolation variability).
Bordering the zone of influence of the Arabian Sea/Indian
Ocean Monsoon, the Arabian peninsula is particularly suscep-
tible in climate to the vagaries of that global climatic feature. At
present, the Arabian Sea Monsoon has direct influence only on
the southern areas of the Arabian peninsula, notably the small
area surrounding Dhufar in southwest Oman, and along western
Yemen and into southwest Saudi Arabia. At various times in the
past (80,000 years before present (YBP), 30,000-35,000 YBP, and
8,000-5,000 YBP), the monsoon influence extended well into
Arabia, to the extent that the present arid areas (precipitation of
some 50-100mm per year) experienced three to five times that
rainfall, transforming much of the desert into a savannah-type
grassland area, still hot, but less dry. Vast lake areas dominated
what is now the 700,000 square kilometres of desert, including
the Ar Rub Al Khali to the south of Saudi Arabia. This standing
water gave rise to extensive human habitation as well as a
hippopotamus and other savannah-type mammals.
Studies of sediment cores taken off the south Yemeni coast
have shown that the monsoonal shifts have occurred through
much of the past 100,000 years over the Arabian peninsula,
with their occurrence related to such items as variation in solar
radiation, snow-pack over northern Europe, the El Niño-
Southern Oscillation (ENSO) system, and so on. These
external and internal (to the Earth’s climate) factors have
caused a waxing and waning of the monsoon’s extension over
the peninsula, and hence to precipitation and habitability
within the peninsula. In addition to the monsoons, other
factors also contribute to local climate, including the semi-
permanent pressure systems, winter-time migratory weather
systems, and topography. The past 5,000 years have in general
been quite dry compared to the geological past, with only
small variations compared to these larger ones of the previ-
ous millennia.
Historical view
Human habitation has reflected this climatological variation,
with periods of more abundance reflecting the availability of
more food and drinking resources in the area. Following the
return of rains to the Arabian peninsula in about 9000 YBP,
thick permanent grassland was established and standing water
was available. These conditions attracted an increasing number
of humans to the area. This new chapter in human habitation
brought a Neolithic Stone Age culture to the region, previously
unknown here. Domestication of the camel and donkey some
millennia later permitted greater wandering, and hence better
adaptation of the peoples to the warmer climate of the past
5,000 years.
At present, the deserts are home to millions of Bedouins and
their means of livelihood, including camels and sheep. Their
nomadic lifestyle has been guided by their historical patterns.
Each tribe has a
dirah
or central part of its range of movement
during the year, and this area includes wells where the tribe
settles for the dry summer months. Each year, based on celes-
tial signs, the Bedouins will depart their summer
dirah
for
winter foraging, and perform the reverse trek. These celestial
The Kingdom of Saudi Arabia:
weather, climate and environment
in a precarious balance
David G. Aubrey, PhD, Woods Hole Group Middle East, representing the
Presidency of Meteorology and Environment, Kingdom of Saudi Arabia
Dr. Sameer A. Bukhari, Presidency of Meteorology and Environment, Kingdom of Saudi Arabia