Transcript Document
Adviser & Head Climate Change Programme, Department of Science & Technology Email: [email protected]
Presentation Outline
Observed Trend in the frequency of extreme weather events over the globe and India Extreme Weather Events and their linkage with CC- Are freak events linked to CC?
How can we reduce the impact of Extreme Weather Events in the Changing Climate?
Summary
Observed Global Trend in the frequency of Extreme Weather events and Sea Level Rise
8 6 10 12 16 14
Annual Frequency of Natural Disasters 1950 – 2005 Flood Storm Earthquake/tsunami, volcanic eruption Others (Heat wave, cold wave, forest fire)
4 2 0 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005
0 50 100 150 200 250
Recent Increasing Trends in Frequency of Natural Hazards
350 300
Windstorms
350 300
Floods
250 200 150 100 50 0 200 150 100 50 0 350 300
Extreme Heat Events
250
Drought
Changes in Sea Level since 1850 and Projection
( IPCC 4thAR, WGI, Paris, 5.2.2007)
Global average sea level has risen since 1961 at an average rate of 1.8mm/yr and since 1993 at 3.1mm/yr
Bangladesh is projected to lose about 16% of its land area with a sea level rise of 1.5 m
Climate Change induced Sea Level Rise may inundate some of the islands of Maldives Sea-Water Inundation Example: Maldives
Area: 115 square miles Population: 143,000 Highest point: 20 ft above sea level
Observed Trend in the frequency of Extreme Weather events and Sea Level Rise over India
Changes in the Frequency of Extreme Rainfall
Low & Moderate events Heavy events (>10cm)
Goswami et al., Science, Dec., 2006
V. Heavy events (>15cm)
Number of Flash Flood Events in India (1980-2006)
Increasing Trend in Flash Flood Events during past 25 years
Total Number of Flood Events in India (1980-2006)
Decreasing Trend in Total Flood Events during past 25 years
6 4 2 0 12 10 8
Decreasing Frequency of Total Number of Cyclonic Storms over India during 1891-2006 y = -0.0183x + 6.3291
R 2 = 0.1031
Y E A R S
Decreasing Disturbances Frequency of Total Number of Cyclonic over India during past 120 years (1891 2009)
Increasing Frequency of Total Number of Low Pressure Areas over India during past 123 years (1888 2009)
Sea Level Rise Observations
• •
Sea-levels increase by ~ 1.3 mm/year Recent ~3.1 mm/year
Climate Projections Av. Surface temperature : increase by 2 - 4
°
C during 2050s Monsoon Rainfall : Marginal changes in monsoon months (JJAS) : Large changes during non-monsoon months No. of rainy days: set to decrease by more than 15 days Intensity of rains : to increase by 1-4 mm/day Cyclonic storms: Increase in frequency and intensity of cyclonic storms is projected
Extreme Events and their linkage with Climate Change
Climate Change and Extreme Weather Events
• • • Climate Change could impact frequency and severity of events on long term and not year to year No clear long term trend is observed in this regard but a number of regions have reported increase in variability. Events which are directly connected to temperature change have shown positive trends
Extreme Events which are directly and indirectly linked to CC
• • Those extreme events which are directly linked to the warming are likely to increase- Heat waves, droughts, extreme rainfall (floods), etc.
Those indirectly related are still doubtful to have been impacted by climate change Increase in number/intensity of cyclones, tornadoes, local severe storms, etc .
Are Freak Extreme Events linked to Climate Change?
Cyclone Phailin: Observed Track
Microwave Imagery of Cyclone Phailin Cloud Bands EYE EYE WALL
Doppler Radar Imagery of Cyclone Phailin
Main Causes of Uttarakhand (Kedarnath) Deluge June 2013
An unconfirmed
cloudburst
event,
Glacier
and
moraine outbursts
,
Steep slopes
associated with the terrain, Sudden
gushing of water and debris
into the valley regions,
Flooding of rivers
on account of incessant rain, Exceeding of
carrying capacity of rivers
, Major
landslides, Panic reactions
of people
High Resolution Satellite Imagery of Uttarakhand Disaster Flow from Glacier (1) Blocked basin created by Moraine-a pool of water was built up
(
2) overtopping of the moraine barrier- resulting in release of impounded water
(
3) Trifurcation of Flow (4) Main Channel of Flow
(
5) Kedarnath Town struck by flow from 2 channels Kedarnath
Uttarakhand Disaster vs Cyclone Phailin
Wx System Size Prediction Accuracy Prediction time Lead time for Disaster management Uttarakhand Phailin Cloud Burst 50 km Cyclone 1000km Poor Very Good 6-12 hrs in advance 3-4 hrs 5-6 days in advance 3-4 days
Key Factors for High Impact of Extreme Events in Developing Population Increase Countries Development /Globalization Increase in Extreme Events
Viewing world through population density
India is one among few countries having very high density of population
Impact of Climate Change on Developing Countries like India
• • •
Impacts are worse
prone and a large share of the economy is in climate sensitive sectors - already more flood and drought
Lower capacity to adapt
financial, institutional and technological capacity and access to knowledge because of a lack of
Climate change is likely disproportionately upon the poorest countries and the poorest persons within countries
inequities in health status and access to adequate food, clean water and other resources.
to impact
, exacerbating
How can we reduce the impact of Extreme Weather Events in the Changing Climate?
VULNERABILITY MAPPING of areas with present and projected scenarios of climate change in relation to extreme events DEVELOPING CAPACITIES TO ADAPT climate change in highly vulnerable regions INCREASING CAPABILITY TO DETECT AND PREDICT extreme events with greater accuracy and longer lead time.
Deploying a MULTI-HAZARD INTEGRATED DECISION SUPPORT SYSTEM PUBLIC AWARENESS about possible impact of climate change and ways & means to cope up
Multi-layered Data Base Management and Modeling Data level Country Model to analyze and predict impact of events to desired level State District Taluk Block Village Multiple Scenario based on data level & event
Integrated Disaster Management Concept Disaster Observation & Monitoring Prediction Advanced & Dense Observational Network Prediction models High resolution Data assimilation High speed computer Impact Assessment Decision Support System Dissemination of Early Warnings
Feedback
Location specific administrative Actions State Gov Village level data bank Decision type Sociological Geo-political Economical Administrative Security Law & Order Data type Geographic Demographic Geo-technical Geological Topographical Meteorological Seismological Communication system
Wide Area network-upto village level Disaster proof-satellite based-2 way
Steps Towards Enhancing Capability to Detect and Predict Extreme Events and Dissemination of Warnings
• • • •
Met. Modernization Plan Prediction Seamless system of Weather Observations and Multi-Hazard Integrated Decision Support System Sub-District level agro-advisory system Outreach- a 24x7 Dedicated Weather Channel