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Environmental Prediction into the Next Decade: Weather, Climate, Water and the Air We Breathe. Incheon, Republic of Korea, 16-17, November 2009. IMPACT OF CLIMATE CHANGE OVER PAKISTAN. Muhammad Touseef Alam. Director. Pakistan Meteorological Department.
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Environmental Prediction into the Next Decade: Weather, Climate, Water and the Air We Breathe Incheon, Republic of Korea, 16-17, November 2009 IMPACT OF CLIMATE CHANGE OVER PAKISTAN Muhammad Touseef Alam Director Pakistan Meteorological Department
The country has a long latitudinal extent stretching from the Arabian Sea in the south to the Himalayan mountains in north It is located in sub-tropics and partially in temperate region Most Parts of Pakistan are Arid to Semi Arid with significant spatial and temporal variability in climatic parameters 59% Annual Rainfall is due to summer monsoons; Greater Himalayan region above 35o N receives winter precipitation mostly in the form of snow and ice.
CLIMATE CHANGE Global Warming Increased Precipitation & its uneven Distribution Melting of Glaciers & Snow Sea level Rise Increase in Frequency & Intensity of Extreme Weather Events IMPACTS Uncertainty in Water Availability Decrease in Crop Yields Loss of Biodiversity Increase Health Risks Climate Change Natural + Anthropogenic Natural Climate Variability Anthropogenic Influences since the Industrial revolution Spiraling Population High pace of Industrialization Increasing use of Fossil Fuels in Industry & Transport Deforestation for Agriculture and Urbanization
Some Recent Climate Extreme Events in Pakistan 2009 Karachi received 205 mm of rain on 18 & 19 July. Heaviest rainfall earlier recorded at Karachi was 207 mm on 1st July, 1977. The normal rainfall at Karachi for the periods 1961-1990 is 85.5 mm 2007 Record heat wave gripped Pakistan during June, 2007. 48°C temperature was recorded on 9th June at Lahore, a record repeated after 78 years. Earlier it was recorded on 8th June 1929
Some Recent Climate Extreme Events in Pakistan • Two super cyclones namely Gonu (02A) of Cat-5 andYemyin (03B) of Cat-1 developed in the Arabian Sea during June,2007and hit Makran Coast and adjoining countries.The history of the Arabian Sea at least during the previous century shows no such events occurring twice in a month 2001 620 mm rainfall recorded in Islamabad during 10 hours in the month of July (on 23rd of July); it caused flooding in Lainullah 1998-2001 History’s worst drought gripped southern parts of Pakistan and parts of surrounding countries
Recent Climate Extremes observed in South Asia and Middle East • 2003 Heavy rains in the holy city of Makkah, Saudi Arabia on November 10; caused widespread flooding of the city • 2005 In India’s western state of Maharashtra, exceptionally heavy rainfall was recorded on July 26 when 944 mm (37.1 in) of rain fell in Mumbai. This was a new all-time 24-hour rainfall for the country, breaking the old record of 838 mm set in Cherrapunji in 1910. Around 1000 people died and damages reached $ 3.5 billion
Recent Climate Extremes observed in South Asia and Middle East • 2004 Snowfall in the al-Jiys mountain range in UAE, the first ever in historical record • 2007 Sidr, a tropical cyclone of Cat-4 slammed ashore of India- Bangladesh border on 15 Nov, 2007. This matched the one in 1991 that sparked tidal wave and killed some 150,000 people
Siachen Glacier Past & Present 1989 2006
Annual Mean Temperature Trend in (°C) in different regions of Pakistan (1951-2000) Regions I (a): Greater Himalayas I (b): Sub-montane II: Western Highlands III Central & Southern Punjab IV Lower Indus Plains V (a) Balochistan Plateau (East) V (b) Balochistan Plateau (West) VI Coastal Areas Negative Trends in Region I b, II and IV; Positive Trends in other regions
Annual % Precipitation Trend in (mm) in different regions of Pakistan (1951-2000) Regions I (a): Greater Himalayas (Winter dominated) I (b): Sub-montane region and monsoon dominated II: Western Highlands III Central & Southern Punjab IV Lower Indus Plains V (a) Balochistan Province (Sulaiman & Kirthar ranges) V (b) Balochistan Plateau (Western) VI Coastal Areas Negative Trends in Region II & VI; Positive Trends in other regions
Percentage Precipitation Changes (on yearly basis) (1951-2000)
Climate Change Trends over Pakistan • The slope of the mean annual temperature over Pakistan during the 48-year period 1960-2007 was found as: 1901-2000 0.06 °C per decade 1960-2007 0.24 °C per decade • The rate of increase is higher than the rate of increase observed globally
Climate Change Projections • Coarse resolution (~300 km x 300 km) projections using Outputs of 17 GCMs for A2, B2 and A1B Scenarios • Fine resolution (~50 km x 50 km)projections by dynamic downscaling of GCM outputs for A2 scenario using RCMs Base period: 1961 – 1990 Futures:2020s = 2010 – 2039 2050s = 2040 – 2069 2080s = 2070 – 2099
GCM-Ensemble based Projected Changes in Annual Average Temperature (°C) and Precipitation in 2080s (A2 Scenario) Temperature Change (°C) Precipitation Change (%)
Projected Temperature Changes in 2080s, ∆T (°C) by GCM Ensemble for A2 Scenario • Temperature increases in both summer and winter are higher in Northern Pakistan than in Southern Pakistan • Temperature increases in Northern and Southern Pakistan are higher in winter than in summer
Projected Precipitation Changes in 2080s, ∆P(%) by GCM Ensemble for A2 Scenario • The rather large errors make it difficult to draw any definite conclusions about change in precipitation with time • There is, however, some indication of precipitation increase in summer and precipitation decrease in winter in the Southern Pakistan
Major Climate Change-related Concerns of Pakistan • Key sectors: Water and Agriculture at greatest risk • Increased risks of floods and landslides, droughts, typhoons and tropical storms, forest fires etc. due to increase in frequency and intensity of extreme events • Severe water-stressed conditions in arid and semi-arid regions due to reduced rainfall, increased temp., and depletion of soil moisture – May lead to expansion of deserts
(Contd.)Major CC-related Concerns of Pakistan • More rapid recession of Hindu Kush (HKH) Glaciers due to increase in temp. and seasonal variability of precipitation may lead to increased summer flows in Indus river system for a few decades, followed by reduction in flows as Glaciers disappear; • Reduction in capacity of natural reservoirs due to rise in snowline on mountains with increase in surface temp. – May increase risk of floods during the wet season; • Agriculture productivity likely to suffer severe losses due to high temp., droughts, flood conditions and soil degradation – Would endanger food security of the country;
(Contd.)Major CC-related Concerns of Pakistan • Large reduction in productivity of both warm water and cold water fish due to oxygen depletion in aquatic systems • As a result of sea level rise, large scale inundation of coastline and recession of flat sandy beaches; upstream incursion of saline water in the Indus delta; and risk to mangroves, coral reefs and breeding grounds of fish • Enhanced risk to life and property in coastal areas due to increased intensity of tropical cyclones, combined with sea level rise; High risk for Karachi and other coastal areas of Sindh-Makran coast
(Contd.)Major CC-related Concerns of Pakistan • Higher incidence of Malaria and other vector-borne, water-borne and heat-related diseases due to warmer and wetter conditions • Risk to fragile ecology of Mountain and Highland systems due to synergetic effects of Climate Change • Increased threat to biodiversity, which is already at risk due to land-use/cover change and population pressure
Concluding Remarks • Temperature increases both past and projected are higher over Pakistan compared to the global changes and as such the country is more vulnerable to climate change. Intensive research is needed to study the adverse impacts of climate change on different socio-economic sectors such as water resources, agriculture production etc. • Pakistan has more glaciers than any other land outside the North and South Poles with sizeable ones in the Karakoram ranges. Glacier melt, in the wake of climate change, is a big threat to the country’s water resources and needs systematic studies to be carried out on the mass balance of glaciers
Contd.. Concluding Remarks • Capacity Building in the use development and modification of mathematical models for use in climate change related studies, needs to be enhanced • A clear cut climate change policy spelling out the government policy and plan of action needs to be formulated to counter the adverse impacts of climate change And finally • This new field of climate change, being an emerging component of natural sciences, needs to be taken up as part of the curricula of studies at the college and university level