By Abdul Qadir Qureshi
(Pakistan News & Features Services)
The problems arising from global warming and emerging serious
water crisis were highlighted at a seminar held at the Federation of Pakistan
Chambers of Commerce and Industry (FPCCI) headquarters in Karachi on July 6.
In a presentation made on the occasion, Shahid Saleem,
Assistant Professor, Sir Syed University of Engineering & Technology
(SSUET), Karachi, stated that global warming, also referred to as climate
change or green house effect, occurs due to burning of fossil fuel like oil,
natural gas, and coal.
“Global warming results in emission of green house (GHG) like
carbon dioxide from power plants, transport, industry; methane from
agricultural activity; nitrous oxide from use of fertilizer and hydroflorcarbon
from industry and refrigeration,” he observed.
Pointing out that that there is a protective layer in
atmosphere over earth called Ozone which is getting depleted due to excessive
GHG emission.
According to him global warming has increased temperature
worldwide by 0.6˚C to 1˚C as per report of Task Committee for Climate Change
and Planning Division, Islamabad. As per the report the temperature would
further increase in future if emission of GHG continues unabated.
Pakistan, he stated, as developing country emits low GHG and
has been ranked 135th in world according to its per
capita GHG emissions. But, with socio-economic development emission of GHG
would increase in future in Pakistan .
Increase in GHG pose serious threat to environment and human
life, he warned and said rise in temperature causes evaporation and
transpiration. Now there is rise in sea level due to expansion of ocean because
of temperature rise and melting of glaciers.
Melting of glaciers causes sudden floods as occurred in
Pakistan in 2010 and 2011. Flood water flows to sea as we do not have
sufficient water storage facility in the country except Mangla Dam, Tarbela Dam
& Chasma Dam reservoirs. Floods also leads to variation in rainfall
occurrence of cyclones while other areas would have long dry spell. Hence drought
conditions would prevail resulting in food shortages.
The present scenario shows there was general tendency
for land use conversation, deforestation or desertification. This situation
has acted as a source of Global Warming. Global Warming is a serious threat
to fresh water.
Shahid Saleem said Pakistan has limited fresh water sources.
Pakistan gets 141 million acre feet (maf) from Indus River System (IRS).
Rainfall and groundwater sources produce another 50 maf of water. Pakistan has
world’s biggest canal network, but it is defective which has resulted in
wastage of water and caused water logging salinity that adversely affected crop
yield. Urban drinking water system found to be equally weak with 35% to 40%
water losses.
“We do not practice conservation of water or recycling of
wastewater. This situation culminated in mismanagement of water sector. Short
supply of water hampered industrial activity. It is through the natural water
cycle that we keep on getting water. But fresh water is receding. It is
imperative to adopt corrective measures urgently”.
Mitigation Measures, he explained, include conservation of
every drop of water to improve irrigation system, reduce water losses in urban
areas, recycle wastewater for non domestic purposes, and enhance water storage
capacity by construction of dams and reservoirs. Regulate out flow of water to
sea to avoid sea intrusion as in case of downstream of Kotri Barrage. Large
scale forestation, large scale tree plantation is necessary. It is important to
create awareness in masses about Global Warming and its preventive measures.
Notwithstanding GHG emissions, he said, Pakistan has to
pursue industrial development essential for its economic development. Through
government and industry joint partnership advanced technologies can be adopted
to capture carbon dioxide, explore possibility to make productive use of CO2,
use alternate or renewable sources of energy, make industrial plant machinery
efficient, and conserve energy.
