Climate Change

6.1 Definition, Causes & Impacts of Climate Change 20812080207820762075207420732072207120702069

Weather is the state of the atmosphere at any instant — short term and can change rapidly. Climate is the long-term pattern of weather in a particular area — seasonal change over decades.

6.1.1 Weather vs Climate 2081

6.1.2 Climate Change & Climate Variability 20812080207820732072207120702069

Climate Change: Refers to seasonal changes over a long period of time caused by both natural factors (volcanic eruptions, ocean currents, orbital changes) and artificial factors (human activities, emission of greenhouse gases). It is the long-term alteration of temperature and typical weather patterns.

Climate Variability: Refers to natural variations in climate that occur over shorter time scales (year-to-year or decade-to-decade), such as El Niño and La Niña events. Unlike climate change, variability represents natural fluctuations around the long-term average.

6.1.3 Extreme Events 2078

1. Droughts: Higher rate of evapotranspiration; desertification can occur. Short but intense rainfall followed by prolonged dry periods.
2. Floods: Extreme precipitation events causing devastating flooding in low-lying areas.
3. Hurricanes/Cyclones: Increased intensity of storms due to warmer ocean surface temperatures.
4. Glacial Lake Outburst Floods (GLOFs): Glacial retreat in the Himalayas threatens catastrophic flooding downstream.
5. Coastal Flooding: Global sea level rose about 8 inches in the last century (rate: 3.2 mm/yr), threatening coastal areas and low-lying islands.

6.1.4 Causes — Natural & Artificial 207520742072

A. Natural Causes:

1. Volcanic Eruptions: Release greenhouse gases, ashes, and dust responsible for global warming.
2. Wind and Ocean Currents: Act as conveyor belts transporting heat and precipitation from the equator to poles, affecting climate.
3. Earth's Orbital Changes: Changes in the tilt of Earth's axis (fluctuates 21.5°–24.5° in 41,000 years) and shape of orbit (elliptical to circular in 100,000 years).
4. Forest Fires: Wildfires destroy forests, which are consumers of CO2, affecting the carbon cycle.
5. Meteor Impacts: Send millions of tons of debris into the atmosphere, blocking sun's rays.

B. Artificial (Human) Causes:

1. Deforestation: Clearing forests for agricultural land reduces CO2 absorption.
2. Burning Fossil Fuels: Factories and power plants emit greenhouse gases.
3. Excessive Use of Automobiles: Vehicle emissions contribute significantly to GHGs.
4. Suburbanization: Urban sprawl increases energy consumption and emissions.

These activities are the highest contributors of greenhouse gases (CO2, CH4, N2O, CFCs).

6.1.5 Impacts of Climate Change 207620742072207120702069

1. Global Temperature Rise & Warming Oceans: Average temperature increased ~1.1°C since 19th century; may warm by 4°C within 83 years. Ocean top 700m shows 0.302°F rise since 1969.
2. Rise of Sea Level & Coastal Flooding: Sea level rose ~8 inches in the last century (3.2 mm/yr).
3. Melting of Glaciers & Polar Ice: Glacial retreat in Himalayas, Alps, Andes, Rockies, Alaska, Africa. Greenland lost 150–250 km³ ice/year (2002–2006). Antarctica lost ~152 km³ (2002–2005).
4. Arctic Sea Ice Loss: Extent and thickness have decreased significantly.
5. Extreme Events: Droughts, intense rainfall, floods, hurricanes; problems in crop yield; desertification.
6. Acid Rain & Ocean Acidification: Surface ocean acidity increased 30% since industrial revolution. CO2 in ocean increasing by 2 billion tons/yr.
7. Migration & Species Extinction: Animals and plants threatened; tropical diseases (malaria, dengue, West Nile) migrate with warming.
8. Health Risks: Spread of vector-borne diseases, heat-related illness.

6.1.6 Greenhouse Gases 2076

The greenhouse effect occurs when CO2, water vapor, and other gases absorb the sun's heat radiated back from Earth's surface. Without GH gases, life on Earth would freeze. With excessive GH gases, the greenhouse effect intensifies and makes Earth excessively warmer.

6.1.7 Impacts in Nepal 20802074207320712070

1. Glacial Retreat & GLOFs: Nepal's Himalayan glaciers are retreating rapidly. Glacial Lake Outburst Floods (GLOFs) threaten downstream communities, infrastructure, and hydropower projects. Nepal holds about 1.054 billion tons of carbon in its forests.
2. Erratic Rainfall Patterns: Changing monsoon patterns; intense short-duration rainfall causing floods and landslides. Drought periods extending, affecting agriculture in the Terai.
3. Agriculture Impact: Changed growing seasons; decline in crop production; extreme events disrupting food supply.
4. Biodiversity Loss: Nepal's rich biodiversity threatened; species migration and habitat disruption in protected areas.
5. Water Scarcity: Reduced snowfall and glacier melt threatening river water supply for drinking, irrigation, and hydropower.
6. Health Risks: Spread of vector-borne diseases (malaria, dengue) to higher elevations as temperatures rise.
7. Deforestation: Nepal's forest cover decline from 57% (1947) to 40.36% (2015) contributes to and worsens climate change impacts.
8. Nepal's NAPA: Nepal launched its National Adaptation Programme of Action (NAPA) in 2010 to address climate vulnerabilities. Nepal even held a cabinet meeting at Mt. Everest to highlight the urgency.

6.1.8 Think Globally, Act Locally 2081

• Local afforestation: Community forest programs (e.g., Nepal’s community forestry) absorb CO2 and protect local ecosystems.
• Clean energy adoption: Promoting biogas, solar power, and improved cooking stoves at the household level reduces emissions.
• Waste management: Local waste segregation, composting, and reduction of open burning decrease methane and CO2 emissions.
• Transport choices: Encouraging cycling, public transport, and electric vehicles in cities reduces fossil fuel dependence.
• Agricultural practices: Sustainable farming, reduced use of chemical fertilizers, and organic farming at the farm level reduce N2O and methane emissions.
• Water conservation: Local watershed management and rainwater harvesting help adapt to changing rainfall patterns.

Thus, while global awareness and international agreements set the direction, the actual reduction in global warming depends on millions of local actions worldwide. As Nepal’s contribution to global emissions is small (~0.027%), local actions in conservation, clean energy, and sustainable practices directly build national resilience against climate change impacts.

Note: Several exam questions in this section also ask about mitigation measures — see Section 6.2 immediately below for appropriate mitigation measures and Nepal-specific adaptation strategies.

6.2 Mitigation Measures of Climate Change 2078207320722069

Climate change mitigation refers to actions for reducing the sources or enhancing the sinks of GHGs. The goal is to stabilize atmospheric greenhouse gas concentrations at a level that would prevent dangerous anthropogenic interference with the climate system.

6.2.1 Mitigation Measures 207820722069

1. A. Carbon Capture:
   • Tree Plantation: Young, fast-growing trees absorb significant CO2. A single tree can absorb 48 lb CO2/year.
   • CCS (Carbon Capture and Storage): CO2 is captured, channeled, and stored permanently in geological formations. The CCS chain: Capture (pre/post-combustion, oxy-fuel) → Transport → Storage (geological, ocean sequestration).
2. B. Energy Sources:
   • Shift from high-CO2 fuels to biodiesel, ethanol
   • Use natural gas instead of coal/oil
   • Develop solar, wind, hydrogen fuel cells
   • Hybrid Electric Vehicles (HEVs)
3. C. International Agreements: International cooperation for GHG reduction; sustainable economic development; international climate laws.

6.2.2 Adaptation from Nepalese Perspective 2073

1. National Adaptation Programme of Action (NAPA): Launched in 2010 to address Nepal's climate vulnerabilities. Identifies priority adaptation needs across sectors. Nepal held a historic cabinet meeting at Mt. Everest (Dec 4, 2009) to highlight urgency.
2. Community Forestry: Nepal's successful community forestry model (forest cover recovered from 29% in 1994 to 40.36% in 2015). 1.054 billion tons of carbon stored in Nepal's forests.
3. Biogas Promotion: Introduced in 1974/75 by United Missions to Nepal. Gobar Gas Company founded 1977. Reduces deforestation for fuelwood.
4. Organic Farming: Reducing N2O emissions from chemical fertilizers; natural methods of pest control; composting.
5. Hydropower Development: Nepal's major renewable energy source; reduces dependence on fossil fuels.
6. Protected Areas: 10 national parks, 6 conservation areas, 3 wildlife reserves protect biodiversity and carbon sinks.
7. GLOF Early Warning Systems: Monitoring glacial lakes to prevent GLOFs.
8. Climate-Resilient Agriculture: Drought-resistant crops, improved irrigation, crop diversification.

6.3 International Efforts to Mitigate Climate Change 208020792078207720762075207320702069

1. UNFCCC (1992): United Nations Framework Convention on Climate Change. Goal: protect the climate system for benefit of present and future generations. Objective: stabilize GHG concentrations to prevent dangerous anthropogenic interference. Adopted 1992, entered into force March 21, 1994. 196 countries participate. Works through annual COP (Conference of Parties). Provides funding, insurance, and technology transfer.
2. Kyoto Protocol (1997): Negotiated Dec 1997 in Kyoto, Japan; in force Feb 16, 2005. Set individual goals for each country. Committed developed countries to reduce GHG emissions by 5.2% by 2012 (vs 1990). Targets 6 greenhouse gases: CO2, CH4, N2O, PFCs, HFCs, SF6.

   Three mechanisms: (a) ETS — Emissions Trading System using Assigned Amount Units (AAUs), (b) CDM — Clean Development Mechanism: invest in GHG-mitigating projects in developing countries, (c) JI — Joint Implementation: emission reduction projects between developed and transition countries.

3. Cancun Adaptation Framework (COP 16, 2010): Adaptation addressed with same priority as mitigation. Country-driven, gender-sensitive, participatory and transparent approach. Guided by best available science and indigenous knowledge. Key goals: implement National Adaptation Programmes of Action (NAPA), build resilience in vulnerable developing countries.
4. Green Climate Fund: Established at COP 16 (2010), operational at COP 17 (Durban, 2011). Objective: paradigm shift towards low-emission, climate-resilient development. Supports developing countries through CDM projects, adaptation programmes. Includes Adaptation Fund, GEF Trust Fund, LDCF, SCCF.
5. Adaptation Fund: Set up under UNFCCC Green Climate Fund. Supports adaptation programmes in developing countries. Financed from CDM projects and developed country donations. Fully operational in 2010.
6. COP 17–23 (Durban to Bonn): Low-carbon society development; Warsaw Loss and Damage Mechanism; agricultural improvement; disaster risk reduction strategies.

6.3.1 Nepal's Alignment with International Efforts 20802079207620732070

1. NAPA Implementation: Nepal launched NAPA in 2010 — must continue implementing priority adaptation projects.
2. CDM Participation: Nepal can attract CDM investments in hydropower, biogas, and forestry projects.
3. Community Forestry & REDD+: Nepal's 40.36% forest cover and 1.054 billion tons carbon can be leveraged under REDD+ for climate financing.
4. Green Climate Fund Access: Nepal should access GCF for adaptation infrastructure: GLOF early warning systems, climate-resilient agriculture, flood protection.
5. Biogas & Renewables: Scale up biogas (already since 1974/75), solar, and micro-hydro programs to reduce fossil fuel dependence.
6. Protected Areas Expansion: Leverage 10 national parks, 6 conservation areas as carbon sinks and biodiversity protection under international agreements.

6.4 Bio-Gas & Organic Farming 20792077

6.4.1 Biogas — Production, Uses & Climate Benefits 20792077

Biogas is produced from the fermentation of biodegradable materials such as sewage, manure, wastewater from livestock farms, and industrial plants. It is a renewable energy source.

Components of Biogas: Methane CH4 (50–70%), CO2 (30–40%), H2 (5–10%), N2 (1–2%), Water Vapour (0.3%), H2S (traces).

Properties: Specific gravity 0.55; ignition temperature 650°C; energy content 6 kWh/m³; digestion temperature 20–35°C; retention period 40–100 days; pH 6–7.

Uses: Generate electricity and heat; fuel vehicles (highly pure only); produce organic fertilizer (fully digested output).

How Biogas Minimizes Climate Change:

1. Reduces Deforestation: Replaces fuelwood for cooking and heating, preserving forests as carbon sinks.
2. Lower Emissions: Burns cleaner than wood or coal; captures methane that would otherwise escape to atmosphere (CH4 is 25 times more potent than CO2 as greenhouse gas).
3. Decentralized Energy: Community-level power generation reduces need for fossil-fuel power plants.
4. Improved Health & Living Standards: Reduces indoor air pollution; end-products are non-polluting and cheap.
5. System is Self-Sustaining: The system pays for itself through fuel and fertilizer savings.

Biogas in Nepal: Introduced in 1974/75 by United Missions to Nepal. In 1977, Agriculture Development Bank and UMN founded the Gobar Gas Company. In 2018, Nepal's first commercial CNG plant (Envipower Energy) began operations.

Risks: Potential gas leaks, fires, explosions; compressed biogas can corrode metals. Safety measures: regularly check for leaks, provide ventilation around gas lines, maintain positive pressure.

Suitability in Terai Region:

1. Warm Climate: Biogas digestion requires 20–35°C. Terai's warm tropical climate is ideal for year-round biogas production with optimal retention period (40–100 days).
2. Livestock Availability: Terai has high concentration of cattle and buffalo, providing abundant raw material (manure).
3. Agricultural Base: Terai is Nepal's agricultural heartland. Biogas produces organic fertilizer as a by-product, benefiting farming.
4. Flat Terrain: Easy construction of biogas plants on flat land.
5. Reducing Deforestation: Replaces fuelwood, reducing pressure on Terai's Chure range forests.
6. Health Benefits: Reduces indoor air pollution from traditional cooking, improving living standards especially for women and children.

6.4.2 Organic Farming 2079

An agricultural method producing vegetables and farm animals using natural nutrient sources (manure, compost, crop residue) instead of synthetic agrochemicals. Also known as low-input farming.

Characteristics:

• Protecting long-term soil fertility through organic matter and biological activity
• Providing crop nutrients through relatively insoluble sources made available by soil micro-organisms
• Nitrogen self-sufficiency through legumes and biological fixation
• Weed, disease, and pest control through crop rotations, natural predators, diversity, organic manuring, resistant varieties

How Organic Farming Minimizes Climate Change:

1. Reduces N2O Emissions: Eliminates chemical fertilizers which are a major source of N2O (GH efficiency 230 times CO2).
2. Reduces Chemical Pollution: No synthetic pesticides or herbicides contaminating soil and water.
3. Improves Soil Carbon Sequestration: Healthy organic soil stores more carbon.
4. Reduces Water & Soil Pollution: Natural methods decrease environmental contamination.
5. Produces Nutritious Food: Long-term benefits to people's health.

6.5 Deforestation and Its Consequences 2077

Deforestation: Conversion of forest to alternative permanent non-forested land use such as agriculture, grazing, or urban development.

6.5.1 Key Facts 2077

• Original forest cover: ~6 billion hectares
• Present forest cover: 30% of world's land (~3.9 billion hectares)
• Earth loses 18.7 million acres of forest each year (~27 football fields/min)
• At current rate: NO MORE RAINFOREST in 100 years
• Deforestation is the 2nd largest anthropogenic source of CO2 (after fossil fuel combustion)
• 1.5 billion tons CO2 released annually from deforestation
• 15% of all GHG emissions come from deforestation (WWF)
• Habitat loss is the main threat to 85% of IUCN "Threatened" and "Endangered" species

6.5.2 Causes of Deforestation

1. Agriculture: Clearing forests for farming land (major cause worldwide and in Nepal)
2. Logging & Fuelwood: 2.6 billion people use biomass (wood, charcoal) for cooking
3. Overgrazing: 20% rise in livestock between 1985–1998; ~10% fodder from forests
4. Fire: 19.8 million ha (1% of all forest) affected by fire annually
5. Mining: Requires large amounts of fuelwood
6. Urbanization & Infrastructure: Land for roads, buildings, railways
7. Illegal Timber Harvesting: Timber smuggling along Nepal-India and Nepal-China borders
8. Other: Tourism, political misuse, cultural practices, natural calamities

6.5.3 Consequences

1. Climate Change: Affects wind flows, water vapor, solar absorption. About 300 billion tons of carbon stored in trees (40 times annual fossil fuel GHG emissions). Nepal's forests contain ~1.054 billion tons carbon.
2. Biodiversity Loss: 80% of world's documented species are in tropical rainforests. Habitat destruction leads to species extinction and human-wildlife conflict.
3. Water Resource Depletion: Deforested areas experience water scarcity.
4. Social Consequences: Loss of ecological services (erosion prevention, flood control, water treatment) affecting poor communities. Tribal communities lose homes.
5. Soil Erosion & Landslides: Loss of root systems destabilizes slopes.
6. Economic Losses: Decline in forest-based livelihoods.
7. Ocean Acidification: Higher atmospheric CO2 leads to more acidic oceans.

6.5.4 Deforestation in Nepal

Highest deforestation rate: 1947–1980 at 2.7% p.a. (57% to 23%). 1980–2000: 1.8% p.a. Recent recovery due to community forestry programs.

6.5.5 Mitigation Measures

• Reduce population growth; increase per capita income
• Increase and improve management of protected areas
• Reserve forests permanently for timber production
• Increase perceived and actual value of forests
• Promote sustainable management; encourage substitutes
• Strengthen institutions and policies; enforce laws (e.g., Paraguay's 2004 Zero Deforestation Law reduced deforestation by 85%)
• Participatory forest management and rights
• Bonn Challenge: restore 150 million ha by 2020 and 350 million ha by 2030

6.6 Importance of National Parks, Conservation Areas & Forestation in Nepal 207820742071

6.6.1 National Parks & Conservation Areas

National Parks: Areas of special scenic, historical, or scientific importance set aside for conservation purposes. Often reserves of natural, semi-natural, or developed land maintained by a national government.

Conservation Areas: Locations receiving protection because of their recognized natural, ecological, or cultural values. Essential for biodiversity conservation, providing habitat and protection for threatened species.

Nepal's Protected Areas: 10 national parks, 6 conservation areas, 3 wildlife reserves.

6.6.2 Importance as GHG Reduction Strategy 2071

1. Carbon Sinks: Nepal's forests contain approximately 1.054 billion tons of carbon. A single tree absorbs 48 lb CO2/year. Protecting forests means preserving these massive carbon stores — 300 billion tons of carbon globally.
2. Biodiversity Protection: 80% of world's documented species live in tropical forests. Protected areas preserve these ecosystems and the ecological services they provide.
3. Water Catchment Protection: Forests regulate water cycles, prevent floods, and maintain water supplies.
4. Soil Conservation: Prevents erosion and landslides; maintains soil fertility.
5. Climate Regulation: Forests affect wind flows, water vapor flows, and solar energy absorption, influencing local and global climate.

6.6.3 Forestation Programs

• Forestation is the establishment of forests where there was no previous tree cover.
• Nepal's community forestry has recovered forest cover from 29% (1994) to 40.36% (2015, DFRS).
• Creates forests, increases carbon capture and sequestration.
• Maintains pleasant climate with adequate rainfall.
• Balances the cycle of oxygen and CO2.
• Improves biodiversity and ground water resources.

The Bonn Challenge aims to restore 150 million ha by 2020 and 350 million ha by 2030 globally.

6.6.4 How to Protect National Parks & Conservation Areas 2074

1. Strengthen Legal Framework: Enforce existing conservation laws and enact stricter regulations against poaching, illegal logging, and encroachment.
2. Community Participation: Involve local communities in conservation through participatory forest management and buffer zone management programs. Community forestry has been Nepal's most successful model.
3. Sustainable Tourism: Promote ecotourism that benefits local communities while minimizing environmental impact. Revenue from tourism funds conservation activities.
4. Anti-Poaching Measures: Strengthen anti-poaching patrols; use technology (drones, camera traps) for wildlife monitoring.
5. Buffer Zone Management: Develop and maintain buffer zones around protected areas to reduce human-wildlife conflict and provide alternative livelihoods.
6. Education & Awareness: Conduct environmental education programs in surrounding communities about the value of conservation.
7. International Support: Access funds from Green Climate Fund, REDD+, and international conservation organizations.
8. Research & Monitoring: Invest in biodiversity research, species monitoring, and ecosystem health assessment for evidence-based management.

Quick-Revision Summary

Chapter 6 — Climate Change — 36 past exam questions

Key Points to Remember

1. Climate change = long-term alteration of temperature & weather patterns (natural + human causes)
2. Climate variability ≠ climate change — variability is short-term natural fluctuations
3. GHG contribution: CO₂ 57%, CFCs 25%, CH₄ 12%, N₂O 6%
4. Kyoto mechanisms: ETS (Emissions Trading), CDM (Clean Development), JI (Joint Implementation)
5. Nepal: 1.054 billion tons carbon in forests; 40.36% forest cover; NAPA launched 2010
6. Biogas: CH₄ 50–70%; introduced Nepal 1974/75; 400,000+ plants installed