7 Climate Change and Disaster Risk Management

Dr. Rajnish Ranjan

Rationale

We often come across the expression that disaster risks are increasing due to climate change or climate change result in more frequent extreme events. This module aims to explore this linkage between climate change and disaster risks and how it can be addressed. Climate change and related concepts are explained first, then the linkage of climate change and disasters is elaborated and finally the institutional and community level actions to address climate change are presented.

Learning objective

• To introduce the concept of climate change
• To understand various models for climate change study
• To describe climate change and disaster linkages
• To understand the national and international initiatives to address climate change

   Unit 1 – Climate Change

Climate is usually defined as the ‘average weather’ or more rigorously as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period is 30 years as defined by the World Meteorological Organization. These relevant quantities are most often surface variables such as temperature, precipitation and wind

The Global Climate Change is one of the most debatable and indispensable topic in the contemporary period inviting attention of almost all sectors of people across the globe.

The United Nations Framework Convention on Climate Change (UNFCCC) defined climate change as a ‘change of climate which is attributed directly or indirectly to human activities that alter the composition of the global atmosphere and which is in addition to natural climate variability observed comparable time periods.

The continuous increase in the global atmospheric temperature and the resultant imbalance in the hydrological cycle led to the change in climatic phenomena which is, thereby, posing challenge to sustainable development.

In order to mitigate the impacts of disasters and /or consequences arising out of the climate change , there is a need to adopt comprehensive policy interventions right from the prevention, preparedness , mitigation to community based approaches and capacity building interventions.

In the year 1988 , World Meteorological Organization (WMO) established the Intergovernmental Panel on Climate Change (IPCC) with the support of UNEP , to bring together the current scientific knowledge and understanding of climate change through its periodic assessment report. IPCC defined “climate change” as “a change in the state of the climate that can be identified by changes in the mean and / or the variability of its properties, and that persists for an extended period, typically decades or longer”.

In 2007 IPCC , observed the following findings on climate change

• “Temperature increases have already affected human, physical, and biological systems. A warming of about 0.2°C per decade is projected.”
• “It is very likely that hot extremes, heart waves, and heavy participation events will continue to become more frequent.”
• “It is likely that future tropical cyclones will become more intense, with grater wind speeds and more heavy precipitation.”
• “Continued greenhouse gas emissions at or above current rates will induce many changes in the global climate system during the 21st century, very likely larger than in the 20th century.”
• “Those with least resources have the least capacity to adapt and are most vulnerable.”

Weather is the set of meteorological conditions – wind, rain, snow, sunshine, temperature, etc. – at a particular time and place. There is a clear difference between global warming and climate change. While the former is defined as in the increase of the earth’s average surface temperature due to a build-up of greenhouse gases in the atmosphere while later is defined in broader term that refers to long-term changes in climate, including average temperature and precipitation.

In climate change phenomena, causes of past changes are not always clear but are generally known to be related to changes in some of the areas like ocean currents, solar activity, volcanic eruptions and other natural factor. Significantly global temperatures have shown rapidly increasing trends over the last few decades, that have impacted in terms of increases in average global air and ocean temperatures, widespread melting of snow and ice, and rising average global sea levels. There are many visible effects of climate change in the agricultural productivity too . Few of them are as under –

    Ø  Loss of biodiversity in fragile environments/tropical forests

Ø  Loss of fertile coastal lands arising out of rising sea levels

Ø  Increased frequencies of weather extremes like floods, droughts, storms etc.

Ø  Long growing seasons in cool areas

Ø  Increased incidences of vector borne diseases and pest

Ø  Dramatic changes in distribution and quantities of fish and sea foods

Long term fluctuations in weather patterns could have extreme impacts on agricultural production , slashing crop yields and forcing farmers to adopt new agricultural practices in response to altered conditions .

It is significant to note that the average global temperature on the earth has increased by about 0.8°C (1.4° Fahrenheit) since 1880. Two-thirds of the warming has occurred since 1975, at a rate of roughly 0.15-0.20°C per decade. Due to continued impact of climate change , every year , different parts of the world witness extreme consequences in the form of urban flooding and other hydro-meteorological disasters. It is difficult to attribute a single event to climate change but the overall risk appears to be increasing . Rising global mean temperature has altered precipitation patterns, atmospheric circulation, hydrological cycle etc. Rising sea level has created sluggish runoff in coastal cities during extreme rainfall events. In addition , there may also be possibility of the higher percentage of cyclone events and more instanes of heavy precipitation combined with higher storm surge . In dense urban agglomeration, urban heat island impact is seen as a major contributor of imbalanced hydrological cycle and consequent occurrence of urban flooding. The increased incidences of heat waves and drought occurrence is also seen as the consequences of climate change. According to De & Sinha Ray (2000) heat wave related deaths were highest (1625) in Rajasthan, followed by Bihar, Uttar Pradesh, Orissa during the period 1978 to 1999. Notably the period roughly coincided with last two decades of the twentieth century which witnessed unprecedented high temperatures globally as a result of the global warming. During the decade 1991-2000 a significant increase in the frequency, persistency and spatial coverage of heat wave / severe heat wave has been observed in comparison to that during the earlier decades 1971-80 and 1981-90

Direct Impact of Climate Change in Urban Agglomeration

Ø  Rise in Sea Level

The mainland of India , endowed with a long coastline of 5,700 km will not escape the wrath of the seas. Total length of the India coastline is about 7500 km (all the island territories of Andaman and Nicobar, and Lakshadweep are taken into account). Approximately 81,000 square km of land fall under LECZ in India, housing a population of over 60 million. 50% of this population is in urban regions comprising approximately 31 million people.Projected sea-level rise along the Indian coast will be between 30 and 80cm over the next century. In the absence of any preventive measures, the people living in coastal areas are potentially going to be affected.

Ø  Impact on Human Health

Climate change is expected to increase environment-related diseases. Warmer and/or wetter period of breeding due to global warming will provide ideal conditions for expansion of mosquito-borne diseases as puddles, in which malaria carrying mosquitoes breed, are created either by excessive rainfall or by droughts in rivers. Lack of sanitation and potable water will increase contaminated water and food-borne diseases like cholera, typhoid, diarrhea, hepatitis, and gastroenteritis. Warmer cities will also induce an increase in respiratory diseases due to pollution whose effects are reinforced by higher temperatures. Changes in temperature and precipitation can spread disease in previously unaffected areas and encourage it in areas already affected.

Modelling climate change

The earth is a complex system that consists of numerous physio-chemical processes that occur at various scales. A simple example is the water cycle that describes how water evaporates from the surface of earth, enters the atmosphere and in this process cools down and condenses to form snow or rain in clouds and finally falls again onto the surface of the earth as precipitation. But modelling a water cycle would be difficult, given the various parameters at work within each of these sub-processes. The concretization during urbanization adds to surface water run-offs that increase water-logging (causing urban floods), which partly percolates into the ground and remaining part runs into the storm water drainages ultimately to enter the rivers or the oceans. Increased evaopration could occur due to increased temperature, deforestation, and heat capture by increased concentration of green-house gases that could lead to increased volume of clouds. These could result in the excessive downpour in short intervals again causing water logging issues.

The physio-geo-chemical processes of the Earth’s climate system could be represented numerically based on laws of physics, chemistry etc. These numerical representations could be run on super computers to analyze the trends and extrapolate with regards to future behaviors of the sub-systems. This modelling of processes in Earth system that leads to particular weather, resulting in climatic conditions of the area under consideration to interpret or predict behvaior in any feasible time scale is termed as climate modelling.

Climate models utilize quantitative methodologies to understand interactions of climatic drivers like the land surface, atmosphere and oceans. The four basic constituents of a climate system are:

1. The Surface

2. The Hydrosphere

3. The Atmosphere

4.  The Cryosphere

The climate models try to determine quantitatively and qualitatively the interactions between the components. Climate modelshelp:

§  gaining insights into behavior of climate systems

§   To arrive at a temporal and spatial description of the system

§   To predict future climate

Types of Climate Models

All four components of climate system cannot be incorporated together due to the myriad interaction and feedback between the components. Thereby climate models usually incorporate a limited number of these interactive processes to aid in computation and modeling.

Climate models are thuscategorized into the following:

1. Energy Balance Models (EBMs): A zero-dimensional Energy Balance Model focuses on the Incoming solar radiation, the emission to outer space due to reflection from Earth, and Earths greenhouse effect- the absorption. If the EBM considers the latitudinal erengy balance (i.e the state of balance of energy between the latitudinal belts on Earth), it is a 1-Dimensional EBM.

2. Radiative-Convective Models (RCMs)–that consider the vertical column energy balance and altitude as the main consideration. The vertical distribution of one or many of the components of the climate system is computed. The heat absorption by the different atmospheric layers is calculated considering the surface temperatures, absorbing/ reflecting capacity, cloud cover, and atmospheric turbidity.

3. Statistical- Dynamical Models (SDMs)- these models consider two dimensions-Horizontal and Vertical, combing the horizontal EBM and the vertical RCM and compute energy diffusion through laws of motion, statistically defining wind speed, direction.

4. General Circulation Models (GCMs)- these models are complex calculations of the functions of atmospheric layers. The coupled atmospheric ocean general circulation model (AOGCM) is one of the most complex models designed.These consider about 10-20 layers in the atmosphere, and about 30 layers in the ocean with a horizontal resolution of 250-600 km. The GCM models energy exchanges and interactions between each of these cells/ layers and arrive at a general model for energy balance taking vertical and horizontal dimensions based on laws of physics. The thermodynamic equations, equations of motion, equations for radiation transfer and equation for water vapor combined with the hydrology of earths surface results in heavy computations of the GCMs which could be downscalled to arrive at smaller resolutions to study the impacts.

   Modeling climate change is very important step to analyze and predict the probability of occurrences of extreme weather events (the hazards) that would aid in better Disaster Risk Reduction measures and to understand the exposure levels at various resolutions and thereby to address vulnerability and for capacity development/ adaptation measures.

Climate Change and India

Developing Nations are believed to be more at risk due to climate change due to the Geography ( non-temperate lattitude), high dependence on agriculture that depends on weather/ climate and greater vulnerability of the population due to lack of investment on vulnerability reduction measures (Stern, 2006).

The following are the effects of Climate Change predicted in India:

·     Declining crop yield

·     Fresh water avaialbility

·     Rising sea levels

·     Increased extreme weather event

·     Loss in biodiversity

·     Higher risk of diseases

India has emphasised the inclusion of Climate Change Adaptation as part of its Intended Nationally Determined Contributions (INDC) (Chaturvedi, 2015).

There have been two India-specific Climate change impact assessments, viz:

1. India’s national Communication to the United Nations Framework Convention on Climate Change(MoEF, 2004)

The study found significant impact on various themes like:

§  Water resources (utilziing Soil and Water Assessment Tools, in combination with output of HadRM2 regional climate model under the IS92a scenario) that the severity of droughts and intensity of floods across the country are likely to increase with few areas having acute water shortages. The changes in evapotranspiration and precipitation are likely to affect ground water levels also affecting water balance.

§  Agriculture sector (using dynamic crop models) could be impacted by reduced productivity mainly due to reduced crop duration.

§  Forest eco-system (BIOME-3 vegetation response model based on HadRM2) showing shifts in forest boundaries and changes in bio-diversity and increase in biotic stress due to reduced adaptability to adverse cliamatic conditions

§  Natural Ecosystem- like grasslands, mangroves and coral reefs are likely to be affected

§  Coastal Zones- flooding , coastal erosion, submergence and coastal ecosystem deterioration are likely impacts

§  Human Health- Projected that malaria would move to higher latitudes and altitudes in India, along with other

§  Infrastructure and energy- the impacts on infrastructure and energy could lead to huge monetary losses, due to downtime, increased demand for water-pumping, space cooling

2. India’s network for Climate Change Assessment for 2030 (INCCA) conceptualized as a network-based scientifc programme to assess the driving factors of climate change and its implications through scientific research, prepare climate change assessments every two years to develop decision support systems and to help in building capacity towards management of climate change related risks and opportunities. The assessment was carried in 4 geographical regions (Himalayan Region, North-Eastern Region, the Western Ghats and Coastal Region) on the 4 key sectors (Agriculture, Water, Natural ecosystem-biodiversity and Health)

Components of Climate Risk Management

There are six components of good climate risk management –

1. Climate risk assessment: assessing priorities, and planning follow up

2. Addressing the consequences: Integrating climate change in programmes & activities

–  Disaster mangement

–  Community risk reduction

–  Health & care

–  Food security

–  Water and sanitation

–  Migration & conflict

3.  Raising awareness

4.  Establishing & enhancing partnerships

5.  International advocacy: shaping the global response to climate change

6.  Documenting & sharing experiences & information

Summary

Lets Summarize this module – Climate is usually defined as the ‘average weather’ or more rigorously as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The United Nations Framework Convention on Climate Change (UNFCCC) defined climate change as a ‘change of climate which is attributed directly or indirectly to human activities that alters the composition of the global atmosphere and which is in addition to natural climate variability observed comparable time periods. In the year 1988 , World Meteorological Organization (WMO) established the Intergovernmental Panel on Climate Change (IPCC) which , in 2007 observed important findings of climate change. There are various direct and indirect impacts observed on the earth due to the possible impact of climate change . In agriculture the main impacts can be seen in the form of losses of biodiversity in fragile environments/tropical forests, losses of fertile coastal lands arising out of rising sea levels , increased frequencies of weather extremes like floods, droughts, storms etc. In order to mitigate the impact climate change, there is a need to adopt a comprehensive policy and plans along with strong commitment of their implementations .

References

• Stern, N. (2006). STERN REVIEW: The Economics of Climate Change Stern Review: The Economics of Climate Change. Government of the United Kingdom.
• MoEF. (2004). India’s Initial National Communication to the United Nations Framework Convention on Climate Change . Government of India.
• Gupta, S., & Sen, P. National and Regional Impacts of Climate Change on the Indian Economy. Delhi School of Economics.
• GEO Umass. (2010, February). Climate Models. Retrieved October 10, 2017, from http://www.geo.umass.edu/courses/geo458/Lectures/Lec7.pdf
• Ramanathan, V., & Coakley-Jr, J. A. (1978). Climate Modeling through Radiative-Convective Models. Reviews of Geophysics and Space Physics, 16 (4), 465-487.
• NISL. (n.d.). Climate Change for Conservation Planning. Retrieved October 10, 2017, from
• NISL  Ecological Informatics: http://planet.botany.uwc.ac.za/nisl/Climate_change/page_57.htm
• Chaturvedi, V. (2015, March). The Costs of Climate Change Impacts for India- A Preliminary Analysis. New delhi, India: Council on Energy, Environment and Water.
• INCCA. (2010). Climate Change and India: A 4×4 Assessment- A Sectoral and Regional Analysis for 2030s. INCCA: Indian Network for Climate Change Assessment.