Climate Change

Climate change is a long-term change (over decades or more) in the average weather pattern – temperature, rainfall, wind, extreme events – of a region or the whole Earth. The present change is mainly due to human activities that increase greenhouse gases (GHGs) in the atmosphere. Global average temperature has already risen by about 1.1 °C above pre-industrial levels (IPCC).

Causes

Natural: changes in solar output, volcanic eruptions, changes in Earth's orbit, ocean currents (El Niño).

Human (anthropogenic) – the main cause today:

1. Burning of fossil fuels (coal, oil, gas) for power, industry and transport – CO₂.
2. Deforestation and land-use change – fewer trees to absorb CO₂.
3. Agriculture – methane from livestock and rice paddies; N₂O from fertilisers.
4. Industrial processes – cement (CO₂), refrigerants (HFCs, CFCs).
5. Waste – methane from landfills.
6. Black carbon – soot from diesel, kilns and cook stoves.

These gases trap heat radiated by the Earth (enhanced greenhouse effect).

Impacts (consequences)

• Rising temperature and more heat waves.
• Melting glaciers and snow – Himalayan glaciers are retreating; risk of GLOF (e.g. Imja and Tsho Rolpa lakes in Nepal).
• Sea level rise – flooding of coastal cities and islands.
• Erratic rainfall – more floods, landslides and droughts; changed monsoon.
• Agriculture – lower yields, crop failure, food insecurity.
• Health – spread of dengue and malaria to new (hill) areas, heat stress.
• Biodiversity loss – species shift upwards or go extinct; coral bleaching.
• Water scarcity – drying springs in Nepal's hills.
• Economic and social – damage to infrastructure and hydropower, migration, poverty.

Climate change is the long-term change in the Earth's average climate – temperature, rainfall, wind and frequency of extreme events – observed over decades or longer. The current rapid change is mainly caused by human activities that add greenhouse gases to the atmosphere. Global temperature has already risen about 1.1 °C above pre-industrial levels (IPCC).

Greenhouse gases and causes

• CO₂ – burning coal, oil and gas; deforestation; cement.
• CH₄ (methane) – livestock, rice paddies, landfills.
• N₂O – chemical fertilisers.
• CFCs/HFCs – refrigerants, aerosols.
• Water vapour and black carbon also add to warming.

These gases let sunlight in but trap outgoing heat – the enhanced greenhouse effect.

Impacts

• Global warming, heat waves, melting glaciers and sea-level rise.
• Irregular monsoon, floods, landslides and droughts.
• Lower crop yields, food and water insecurity.
• Spread of vector-borne diseases (dengue, malaria) to higher areas.
• Biodiversity loss.
• In Nepal: temperature is rising faster than the global average in the mountains; glacial lakes are growing (GLOF risk); springs are drying; Nepal is among the most vulnerable countries although it contributes a tiny share (well under 0.1%) of global emissions.

Responses

• Mitigation – cut emissions: renewable energy, energy efficiency, electric transport, forest protection (REDD+).
• Adaptation – adjust to impacts: drought-resistant crops, early warning systems, LAPA/NAP in Nepal.
• International efforts – UNFCCC (1992), Kyoto Protocol (1997), Paris Agreement (2015) to keep warming well below 2 °C and pursue 1.5 °C.

Deforestation is the permanent removal or large-scale clearing of forests and their conversion to other land uses such as farmland, settlements or infrastructure. Nepal's forest cover fell sharply up to the 1990s; community forestry has since helped forest cover recover to about 45% (Forest Resource Assessment), but forests are still lost in the Terai and the Chure (Siwalik) range.

Causes in Nepal

1. Population growth and agricultural expansion – clearing forests for farmland, especially in the Terai after malaria eradication and migration from the hills.
2. Fuel wood demand – a large share of households cook with firewood.
3. Timber smuggling and illegal logging.
4. Infrastructure – roads (often without proper planning), hydropower, transmission lines, airports, settlements.
5. Encroachment and squatter settlements in forest land.
6. Overgrazing and fodder collection.
7. Forest fires, often human-caused, increasing in dry springs.
8. Mining of sand, gravel and stone, especially in the Chure.
9. Weak governance – poor law enforcement and political interference.

Impacts (consequences)

1. Soil erosion and landslides – loss of root cover on steep slopes; more landslides in the monsoon.
2. Floods and sedimentation – rivers carry more sediment, filling reservoirs and damaging hydropower and irrigation; Terai floods increase.
3. Drying of springs and water sources – less infiltration and groundwater recharge.
4. Loss of biodiversity – habitat loss for tigers, rhinos, red pandas and medicinal plants.
5. Climate change – forests store carbon; clearing releases CO₂ and reduces carbon sinks.
6. Desertification of the Chure, affecting Terai agriculture.
7. Hardship for rural people – women walk farther for firewood and fodder; loss of forest-based income.
8. Loss of tourism and cultural value.

Remedies: community and leasehold forestry, afforestation, President Chure-Tarai Madhesh Conservation Programme, alternative energy (biogas, electricity), strict control of illegal logging and REDD+.

Organic farming is a system of agriculture that produces crops and livestock without synthetic chemical fertilisers, pesticides, herbicides, growth hormones or genetically modified organisms. It depends on natural inputs and ecological processes – compost, farmyard manure, green manure, crop rotation, biological pest control – to keep the soil fertile and control pests.

Typical organic farming practices

• Compost, vermicompost and farmyard manure for nutrients.
• Crop rotation and inter-cropping (e.g. legumes with cereals to fix nitrogen).
• Green manuring and mulching.
• Bio-pesticides (neem, jholmal, cow urine-based sprays) and natural predators.
• Mixed farming – crops with livestock.
• Use of local seeds.

Advantages

1. Healthy food – free from chemical residues; safer for consumers.
2. Improves soil health – more organic matter, better structure, water holding and microbial life; long-term fertility.
3. Protects the environment – no nitrate and pesticide pollution of rivers and groundwater; less eutrophication.
4. Protects farmers' health – no exposure to toxic sprays.
5. Conserves biodiversity – pollinators (bees), birds and soil organisms survive.
6. Climate benefits – stores carbon in soil; less energy for making chemical fertilisers; lower N₂O emissions.
7. Low input cost – uses local, on-farm resources; less dependence on imported fertiliser (important for Nepal).
8. Higher price and export market – organic tea, coffee, cardamom, honey and vegetables fetch premium prices.
9. Sustainability – suits small hill farms in Nepal; several districts and provinces (e.g. Karnali) promote organic farming.

Limitations: lower yields at first, more labour, need for certification and markets.

Climate resilience is the ability of people and ecosystems to absorb, cope with and recover from climate shocks (floods, droughts, landslides, fires) and adapt to long-term change. In Nepal, protected areas and forest programmes are a core part of this.

Effectiveness of national programmes

Overall: these programmes have been effective – protected areas cover about 23–24% of the country, forest cover has increased to about 45%, and tiger and rhino numbers have risen. They protect water sources and slopes and give communities funds and local institutions that can respond to climate risks. Gaps remain in fire control, invasive species, equity and climate-proof planning.

Support from international climate agreements

1. Finance – the Paris Agreement and UNFCCC funds (Green Climate Fund, Global Environment Facility, Adaptation Fund) finance adaptation and forestry projects in Nepal.
2. REDD+ – payments for reducing emissions from deforestation; Nepal's Terai Arc emission-reduction programme under the World Bank FCPF rewards community forests.
3. Technology and capacity – training, monitoring tools, early warning systems.
4. Framework for plans – Nepal's NDC, National Adaptation Plan (2021) and LAPA are linked to UNFCCC processes.
5. Loss and Damage Fund (agreed at COP27/28) – support for climate-hit communities.
6. Global mitigation – only global emission cuts can limit warming that threatens Nepal's glaciers.
7. CBD and Ramsar – support for biodiversity and wetland conservation.

Climate

Climate is the average weather of a place over a long period, usually 30 years or more – its typical temperature, rainfall, humidity and wind. E.g. the Terai has a hot, humid sub-tropical climate.

Climate variability

Climate variability is the natural short-term fluctuation of climate around its long-term average – from season to season or year to year – such as a drier monsoon one year or a cold winter in another, caused by El Niño/La Niña, ocean–atmosphere cycles or volcanoes. It does not imply a long-term trend.

Human-induced climate change

Human-induced (anthropogenic) climate change is the long-term change in the global climate caused by human activities that increase greenhouse gases – mainly burning fossil fuels, deforestation, agriculture and industry – which enhance the greenhouse effect and warm the Earth. The IPCC states that human influence has unequivocally warmed the planet by about 1.1 °C since pre-industrial times.

Importance of collective international efforts

1. Global problem – GHGs mix in the whole atmosphere; emissions from any country affect all. No country can solve it alone.
2. Unequal responsibility – developed countries and large emitters caused most emissions, while poor countries like Nepal (well under 0.1% of global emissions) suffer most. The principle of common but differentiated responsibilities needs international agreement.
3. Avoid free-riding – a binding framework (UNFCCC, Kyoto Protocol, Paris Agreement) makes each country commit through NDCs and report progress.
4. Finance – adaptation and clean energy need money; the Green Climate Fund and Loss and Damage Fund move funds from rich to vulnerable countries.
5. Technology transfer – renewable energy, efficient technologies and early warning systems spread faster through cooperation.
6. Science and data – the IPCC pools scientists from all countries to assess risk.
7. Trans-boundary impacts – Himalayan glacier melt affects rivers flowing through Nepal, India, Bangladesh and China; regional cooperation (e.g. ICIMOD) is needed.
8. Shared target – keeping warming well below 2 °C and aiming for 1.5 °C is possible only if all major emitters act together.

Responses to climate change are of two kinds: mitigation (reducing the cause) and adaptation (reducing the harm).

Mitigation

Mitigation means actions that reduce greenhouse gas emissions or increase carbon sinks, so that warming is limited.

• Shift to renewable energy – hydropower, solar, wind, biogas.
• Energy efficiency – LED lights, efficient motors, better buildings.
• Electric transport and public transport (Nepal's hydropower suits EVs).
• Forest conservation, afforestation and REDD+.
• Clean cooking – electric/induction cookers, improved stoves.
• Sustainable agriculture, less methane from waste (composting, landfill gas capture).
• Carbon pricing and cleaner industrial processes.

Adaptation

Adaptation means adjusting human and natural systems to cope with actual or expected climate impacts.

• Drought- and flood-tolerant crop varieties, changed cropping calendars.
• Water harvesting, spring recharge ponds, irrigation.
• Early warning systems for floods and GLOFs (e.g. lowering of Imja and Tsho Rolpa glacial lakes).
• Climate-resilient roads, bridges and hydropower design.
• Disaster preparedness and insurance.
• Health measures against dengue and heat stress.
• Plans in Nepal: NAPA (2010), LAPA (2011), National Adaptation Plan (2021).

Both are needed: mitigation limits future damage; adaptation deals with change already happening.

Weather is the state of the atmosphere at a particular place and time – temperature, rainfall, humidity, wind, cloud – which changes from hour to hour and day to day (e.g. "it is raining in Pokhara today"). Climate is the average weather of a place over a long period, usually 30 years or more (e.g. "Pokhara has a wet sub-tropical climate").

International efforts on mitigation and adaptation

1. IPCC (1988) – assesses climate science; its reports guide policy.
2. UNFCCC (1992, Rio Earth Summit) – framework treaty; annual COP meetings; principle of common but differentiated responsibilities.
3. Kyoto Protocol (1997) – binding emission cuts for developed countries (about 5% below 1990 levels in 2008–2012); Clean Development Mechanism allowed projects such as Nepal's biogas to earn carbon credits.
4. Paris Agreement (2015) – all countries submit NDCs; goal to keep warming well below 2 °C and pursue 1.5 °C; net-zero by the second half of the century; global stocktake every five years.
5. Montreal Protocol (1987) and its Kigali Amendment (2016) – phase out CFCs and HFCs.
6. Climate finance – Green Climate Fund, Adaptation Fund, GEF, Loss and Damage Fund (COP27/28).
7. Adaptation programmes – National Adaptation Plans, LDC Fund; Nepal's NAPA, LAPA and NAP.
8. REDD+ – payments for forest conservation.

Why these efforts help create a better Earth

1. Limit warming – global cooperation has already lowered projected warming compared to the no-policy path; renewable energy is now the cheapest new power in most countries.
2. Protect ecosystems – limiting warming to 1.5 °C saves far more coral reefs, glaciers and species than 2 °C.
3. Cleaner air and better health – cutting fossil fuels reduces air pollution deaths.
4. Resilient communities – adaptation funding builds early warnings, resilient crops and infrastructure; fewer lives lost to floods and GLOFs.
5. Justice for vulnerable countries – finance and technology transfer help countries like Nepal that emit little but suffer much.
6. Green economy – new jobs in solar, EVs, efficiency; sustainable development (SDG 13).
7. Proven success – the Montreal Protocol is healing the ozone layer, showing that collective action works.

However, current NDCs are still not enough for 1.5 °C, and promised finance is often delayed; stronger and fair implementation is needed for these efforts to deliver a better future Earth.

Human-induced (anthropogenic) climate change is the long-term change in the Earth's climate caused by human activities that increase the concentration of greenhouse gases (GHGs) and change land surfaces, beyond natural climate variability. According to the IPCC it is unequivocal that human influence has warmed the planet – by about 1.1 °C since pre-industrial times.

Mechanism

GHGs (CO₂, CH₄, N₂O, CFCs) let sunlight through but absorb the heat radiated from the Earth, warming the lower atmosphere. Human activities strengthen this natural effect – the enhanced greenhouse effect. Atmospheric CO₂ has risen from about 280 ppm before industrialisation to over 420 ppm today.

Human causes

1. Burning fossil fuels for electricity, industry and transport – the largest source of CO₂.
2. Deforestation and land-use change – releases stored carbon and removes sinks.
3. Agriculture – methane from livestock and paddy fields; N₂O from fertilisers.
4. Industry – cement, steel, chemicals; HFCs from cooling.
5. Waste – methane from landfills and sewage.
6. Black carbon from diesel, brick kilns, cook stoves.
7. Urbanisation – heat islands, high energy use.

Impacts

Global warming, glacier melt and GLOF risk in the Himalaya, sea-level rise, irregular monsoon, floods and droughts, food insecurity, spread of diseases and loss of biodiversity.

Control

Renewable energy, energy efficiency, forest conservation, sustainable agriculture, and international agreements such as the Paris Agreement.

Biogas is a combustible gas produced when organic matter (biomass) – cattle dung, human excreta, kitchen waste, crop residue – is decomposed by bacteria in the absence of oxygen (anaerobic digestion). It contains about 50–70% methane (CH₄) and 30–40% CO₂, with small amounts of H₂S and water vapour.

Process (anaerobic digestion)

1. Hydrolysis – complex organics (carbohydrates, proteins, fats) broken into simple sugars, amino acids and fatty acids.
2. Acidogenesis – converted into volatile fatty acids, alcohol, CO₂ and H₂.
3. Acetogenesis – converted into acetic acid, H₂ and CO₂.
4. Methanogenesis – methanogenic bacteria produce CH₄ and CO₂.

 Dung + water -> [Inlet] -> [Digester] -> gas -> stove
                              |
                          [Outlet] -> slurry -> fertiliser

Conditions: temperature about 30–40 °C (mesophilic), pH about 6.8–7.5, airtight digester, proper dung–water mix (about 1:1).

Benefits

• Clean cooking and lighting fuel; replaces firewood and kerosene.
• Reduces indoor air pollution and eye/lung disease.
• Slurry is a rich organic fertiliser.
• Reduces deforestation and methane release from open dung; earns carbon credits (Nepal's biogas programme was registered under the CDM).
• Improves sanitation when toilets are connected.
• Saves women's time spent collecting firewood.

In Nepal: the Biogas Support Programme and AEPC have helped install several hundred thousand household plants, mostly the GGC-2047 fixed-dome model.

Limitations: needs cattle and water, lower gas output in cold hills in winter, initial cost.

Climate change is a global problem caused by greenhouse gases from all countries, so it needs international cooperation. The main efforts to mitigate it are:

1. IPCC (1988) – set up by WMO and UNEP to assess climate science; its reports form the scientific basis of negotiations.
2. UNFCCC (1992) – adopted at the Rio Earth Summit; aim to stabilise GHG concentrations at a safe level; parties meet yearly at the Conference of the Parties (COP); principle of common but differentiated responsibilities.
3. Kyoto Protocol (1997, in force 2005) – first binding targets: developed (Annex I) countries to cut emissions about 5% below 1990 levels in 2008–2012. Introduced emissions trading, Joint Implementation and the Clean Development Mechanism (CDM).
4. Paris Agreement (2015, COP21) – all countries set Nationally Determined Contributions (NDCs); goal to keep warming well below 2 °C and pursue 1.5 °C; five-yearly global stocktake; climate finance commitments. Nepal ratified it in 2016 and has a net-zero target for 2045.
5. Montreal Protocol (1987) and Kigali Amendment (2016) – phasing out CFCs and HFCs, which are also strong greenhouse gases.
6. REDD+ – rewards developing countries for reducing deforestation.
7. Climate funds – Green Climate Fund, Global Environment Facility, Adaptation Fund, and the Loss and Damage Fund (COP27–28).
8. Glasgow (COP26) – agreed to "phase down" coal and cut methane (Global Methane Pledge).
9. COP28 (Dubai) – first global stocktake; call to transition away from fossil fuels.

Limitations: pledges are still not enough for 1.5 °C, finance falls short, and big emitters sometimes withdraw (e.g. the USA left the Paris Agreement under different administrations).

Climate change is the long-term change in the Earth's average temperature and weather patterns, mainly caused by greenhouse gases released by human activities such as burning fossil fuels and deforestation. Its effects include global warming, melting glaciers, sea-level rise, erratic rainfall, floods, droughts and loss of biodiversity.

Alternative (renewable) energy

Renewable energy comes from sources that are naturally replenished – hydropower, solar, wind, biomass/biogas, geothermal and micro-hydro – and produces little or no greenhouse gas during operation.

Usefulness of renewable energy regarding climate change

1. Mitigation – reducing emissions

• Replaces coal, oil and gas in electricity, so CO₂ emissions fall sharply; the energy sector is the largest source of global emissions.
• Electric vehicles powered by hydropower cut transport emissions – very relevant for Nepal, which imports all petroleum.
• Electric/induction cooking and biogas replace firewood and LPG, reducing CO₂ and black carbon.
• Biogas captures methane from dung that would otherwise escape.
• Less firewood demand means less deforestation, keeping forests as carbon sinks.

2. Adaptation and resilience

• Decentralised energy (solar home systems, micro-hydro, mini-grids) keeps remote villages supplied when floods or landslides cut the grid.
• Solar water pumps support irrigation during droughts.
• Energy for cold storage, communication and early-warning systems.

3. Co-benefits

• Cleaner air in cities and homes – fewer respiratory diseases.
• Energy security and less spending on imported fuel (petroleum imports are a large share of Nepal's trade deficit).
• Jobs and local industry (solar installers, biogas masons, micro-hydro operators).
• Rural electrification and better education and health services.

4. Nepal's context

• Large hydropower potential, good solar radiation (about 300 sunny days a year), widespread biogas (several hundred thousand plants) and micro-hydro.
• Nepal's NDC and long-term strategy aim for net-zero emissions by 2045 using hydropower, EVs and clean cooking; exporting clean electricity to India and Bangladesh can help reduce regional emissions.

Limitations: high initial cost, intermittency of solar and wind (needs storage), seasonal variation of run-of-river hydropower, and climate risks to hydropower itself (GLOF, sediment). Proper planning and storage projects are needed.

Nepal is one of the countries most vulnerable to climate change, although its share of global greenhouse gas emissions is tiny (well under 0.1%). Its fragile mountains, dependence on rain-fed farming and poverty magnify the impacts. Studies by DHM show maximum temperature rising by about 0.05 °C per year, faster at higher altitudes.

Impacts of climate change in Nepal

1. Glacier retreat and GLOF risk – Himalayan glaciers are shrinking; glacial lakes such as Imja, Tsho Rolpa and Thulagi are growing and could burst (glacial lake outburst flood), threatening villages and hydropower downstream.
2. Erratic monsoon – late onset, intense short rainfall, long dry spells; more floods in the Terai (e.g. 2017 floods) and landslides in the hills.
3. Drying springs and water scarcity in the mid-hills, increasing women's workload.
4. Agriculture and food security – lower yields of rice, wheat and maize due to drought, heat and new pests; shift of crops upwards (apples moving to higher altitude in Mustang).
5. Health – dengue, malaria and kala-azar spreading to hills (dengue outbreaks in Kathmandu, 2019 and 2022), heat stress in the Terai.
6. Biodiversity – tree line and species moving upward, invasive species spreading, wetlands drying.
7. Hydropower – changes in river flow and higher sediment load affect generation and damage turbines.
8. Forest fires – longer dry seasons cause more fires in spring.
9. Tourism – loss of snow and unstable trekking routes; disasters affect visitors.
10. Livelihoods and migration – poor and marginalised people lose income and migrate.

International efforts towards mitigation of climate change

1. IPCC (1988) – provides scientific assessments.
2. UNFCCC (1992) – framework convention; annual COPs; common but differentiated responsibilities.
3. Kyoto Protocol (1997) – binding cuts for developed countries (about 5% below 1990 levels in 2008–2012); emissions trading and CDM (Nepal's biogas earned carbon credits).
4. Paris Agreement (2015) – all countries give NDCs; goal well below 2 °C, pursue 1.5 °C; climate finance; global stocktake. Nepal ratified it in 2016 and committed to net-zero by 2045.
5. Montreal Protocol and Kigali Amendment – phase-out of CFCs and HFCs.
6. REDD+ – payments for forest conservation; Nepal's Terai Arc programme is part of it.
7. Finance mechanisms – Green Climate Fund, GEF, Adaptation Fund, LDC Fund, and the new Loss and Damage Fund.
8. Regional cooperation – ICIMOD (based in Kathmandu) works on Hindu Kush Himalaya climate research.

Nepal uses these platforms to demand finance and technology as a least-developed mountain country, through its NAPA (2010), LAPA, National Climate Change Policy (2019) and National Adaptation Plan (2021).

Global warming is the long-term rise in the average temperature of the Earth's surface and lower atmosphere, mainly due to the increase of greenhouse gases (CO₂, CH₄, N₂O, CFCs) from human activities such as burning fossil fuels, deforestation and agriculture. These gases trap infrared heat radiated by the Earth (enhanced greenhouse effect). The Earth has warmed about 1.1 °C since pre-industrial times.

 Sunlight --> Earth surface --> heat (IR) out
                                   |
              GHG layer traps part, re-emits down
                                   |
                         warmer lower atmosphere

Effects: melting glaciers and polar ice, sea-level rise, heat waves, erratic rainfall, floods and droughts, and loss of biodiversity.

International efforts to mitigate global warming

1. IPCC (1988) – scientific assessment of climate change.
2. UNFCCC (1992) – global framework; annual COP meetings.
3. Kyoto Protocol (1997) – binding emission cuts for developed countries; carbon trading and CDM.
4. Paris Agreement (2015) – NDCs from all countries; keep warming well below 2 °C, aim for 1.5 °C.
5. Montreal Protocol (1987) / Kigali Amendment (2016) – phase out CFCs and HFCs.
6. REDD+ – forest conservation incentives.
7. Climate finance – Green Climate Fund, Adaptation Fund, Loss and Damage Fund.
8. Recent COPs – Glasgow (coal phase-down, methane pledge), Dubai COP28 (transition away from fossil fuels).

Climate change is a long-term change (over decades or longer) in the average weather pattern of the Earth or a region, such as temperature, rainfall and wind. The present climate change is mainly caused by human activities that increase greenhouse gases (GHGs) in the atmosphere, leading to global warming. The Earth is already about 1.1–1.2 °C warmer than in pre-industrial times (IPCC AR6).

Gases that cause climate change

Greenhouse gases let sunlight pass through but absorb the long-wave heat radiated back by the Earth, and re-emit part of it towards the surface. This is the greenhouse effect. A natural greenhouse effect keeps the Earth at about 15 °C instead of −18 °C; extra GHGs from human activity make it stronger.

           Sun (short-wave radiation)
                  |
                  v
   ======== atmosphere with GHGs ========
     ^   some heat escapes     |  GHGs absorb and
     |                         v  re-emit heat back
   ----------- Earth's surface ------------
     (absorbs light, emits long-wave heat)

• Carbon dioxide (CO₂) is the most important gas because of its huge quantity. Its concentration has risen from about 280 ppm before the Industrial Revolution to over 420 ppm today, mainly from fossil fuels and loss of forests.
• Methane (CH₄) comes from anaerobic decomposition in rice fields, livestock digestion, landfills and leaks from gas wells. It traps about 28 times more heat than CO₂ per kg over 100 years.
• Nitrous oxide (N₂O) is released from chemical fertilisers, animal waste and biomass burning. It is long-lived and also damages the ozone layer.
• Halocarbons (CFCs, HCFCs, HFCs) are man-made gases from refrigeration and air conditioning. CFCs also destroy stratospheric ozone; they are controlled by the Montreal Protocol (1987) and HFCs by its Kigali Amendment (2016).
• Water vapour is the most abundant natural greenhouse gas. It is not emitted directly by people, but warmer air holds more of it, so it amplifies warming (positive feedback).
• Ozone and black carbon (soot from brick kilns, diesel and firewood) are short-lived climate pollutants. Black carbon deposited on snow makes it darker, so glaciers melt faster.

Major symptoms of climate change in Nepal

Nepal is a mountain country with fragile geology, so it shows the signs of climate change clearly:

• Rising temperature: DHM data show average maximum temperature rising by about 0.06 °C per year, faster in the mountains than in the Terai.
• Glacier retreat and snow loss: Himalayan glaciers are thinning and retreating; snow lines are moving up and snow-capped peaks are turning into bare rock.
• Glacial lake growth and GLOF risk: lakes such as Tsho Rolpa and Imja Tsho are expanding. ICIMOD (2020) listed 47 potentially dangerous glacial lakes in the Koshi, Gandaki and Karnali basins (21 of them in Nepal).
• Erratic monsoon: late onset, fewer rainy days but more intense rain, causing both floods and drought in the same year.
• More floods, landslides and debris flows: e.g. the 2021 Melamchi flood and the 2024 Kathmandu valley floods.
• Drying of springs and water sources in the middle hills, forcing people to migrate.
• Agricultural changes: crop failure, new pests and diseases, upward shift of crops (apple farming moving to higher altitudes such as Mustang).
• Health effects: spread of malaria, dengue and other vector-borne diseases to hill areas (dengue now reaches Kathmandu and above).
• Biodiversity shift: species and tree lines moving upward; invasive species spreading.
• Forest fires in dry winter and pre-monsoon seasons are becoming more frequent.

These symptoms threaten Nepal's water resources, hydropower, agriculture, tourism and the lives of people living in the hills and mountains.

Climate change gases (greenhouse gases, GHGs) are gases in the atmosphere that absorb and re-emit long-wave (infrared) heat radiated by the Earth. Their increase due to human activity strengthens the greenhouse effect and causes global warming and climate change.

CO₂ contributes the largest share of warming because of its quantity; methane and N₂O are much stronger per kg; halocarbons are both GHGs and ozone-depleting.

Probable impacts of climate change

1. Rise in temperature and heat waves: more extreme hot days, heat stress on people and animals.
2. Melting of glaciers and ice sheets: Himalayan glaciers retreat; formation of glacial lakes and risk of GLOF (glacial lake outburst floods). Long term, rivers fed by snow lose dry-season flow.
3. Sea level rise: thermal expansion and ice melt flood low-lying coasts and islands (Maldives, Bangladesh).
4. Changed rainfall: heavier floods in some areas, longer droughts in others; erratic monsoon.
5. Agriculture and food security: lower yields, new pests, shifting crop zones.
6. Water scarcity: springs dry up, groundwater falls.
7. Health: spread of malaria, dengue, cholera; heat-related deaths; malnutrition.
8. Biodiversity loss: species migrate upward or become extinct; coral bleaching; forest fires.
9. Economic loss: damage to roads, hydropower and settlements; poverty and climate migration.
10. Ocean acidification: CO₂ dissolved in the sea harms shellfish and coral.

Mitigation measures

Mitigation means reducing GHG emissions or increasing their removal (sinks).

• Clean energy: expand hydropower, solar, wind and micro-hydro; phase down coal, oil and gas.
• Energy efficiency: LED lights, efficient motors, better building insulation, energy audits in industry.
• Clean transport: electric vehicles and electric public transport, cable cars, non-motorised transport (cycling, walking).
• Forests and land: stop deforestation, plant trees, community forestry, REDD+ (Reducing Emissions from Deforestation and Forest Degradation).
• Agriculture: less chemical fertiliser, organic farming, better manure handling, improved paddy water management.
• Waste: reduce, reuse, recycle; capture landfill methane; biogas from kitchen and animal waste.
• Industry: cleaner production, replacing old brick kilns with zig-zag kilns, low-carbon cement.
• Carbon pricing and policy: carbon tax, emissions trading, removing fossil fuel subsidies.
• Awareness and lifestyle: saving energy, less food waste, using public transport.

Along with mitigation, countries also need adaptation (e.g. GLOF early warning, drought-resistant crops, climate-proof infrastructure) because some warming is already locked in.

Climate change is a significant long-term change in the average weather (temperature, rainfall, wind, seasons) of a place or of the Earth as a whole. The present change is mainly due to human emission of greenhouse gases, which trap extra heat and cause global warming.

Gases causing climate change

Greenhouse gases are transparent to incoming sunlight but absorb outgoing infrared heat from the Earth and send part of it back, warming the lower atmosphere.

           Sun (short-wave radiation)
                  |
                  v
   ======== atmosphere with GHGs ========
     ^   some heat escapes     |  GHGs absorb and
     |                         v  re-emit heat back
   ----------- Earth's surface ------------
     (absorbs light, emits long-wave heat)

• Carbon dioxide (CO₂) is the most important gas because of its huge quantity. Its concentration has risen from about 280 ppm before the Industrial Revolution to over 420 ppm today, mainly from fossil fuels and loss of forests.
• Methane (CH₄) comes from anaerobic decomposition in rice fields, livestock digestion, landfills and leaks from gas wells. It traps about 28 times more heat than CO₂ per kg over 100 years.
• Nitrous oxide (N₂O) is released from chemical fertilisers, animal waste and biomass burning. It is long-lived and also damages the ozone layer.
• Halocarbons (CFCs, HCFCs, HFCs) are man-made gases from refrigeration and air conditioning. CFCs also destroy stratospheric ozone; they are controlled by the Montreal Protocol (1987) and HFCs by its Kigali Amendment (2016).
• Water vapour is the most abundant natural greenhouse gas. It is not emitted directly by people, but warmer air holds more of it, so it amplifies warming (positive feedback).
• Ozone and black carbon (soot from brick kilns, diesel and firewood) are short-lived climate pollutants. Black carbon deposited on snow makes it darker, so glaciers melt faster.

Possible interventions to mitigate climate change

1. Energy sector (largest source of CO₂)

• Shift from coal, oil and gas to renewable energy: hydropower, solar, wind, geothermal, biogas.
• Improve efficiency in power plants, buildings, appliances and industry.

2. Transport

• Electric vehicles and electric mass transit (e.g. Nepal's electric buses and reduced customs duty on EVs).
• Better urban planning, cycling lanes, footpaths.

3. Forestry and land use

• Stop deforestation, afforestation and reforestation; community forestry (Nepal's forest cover has risen to about 45%).
• REDD+ payments for keeping forests standing.

4. Agriculture

• Organic farming and balanced fertiliser use to cut N₂O.
• Improved rice cultivation (alternate wetting and drying) to cut methane; biogas from dung.

5. Industry and waste

• Cleaner brick kilns, low-clinker cement, recycling.
• Landfill gas capture, composting, waste-to-energy.

6. Policy and economic tools

• Carbon tax, emission trading, removal of fossil-fuel subsidies, green building codes.
• Climate finance and technology transfer to developing countries.

7. International cooperation

• UNFCCC, Kyoto Protocol, Paris Agreement and NDCs; Montreal Protocol and Kigali Amendment for halocarbons.

8. Research and technology

• Carbon capture and storage, green hydrogen, better batteries.

9. Awareness and behaviour

• Saving energy, using public transport, reducing food waste, sustainable consumption.

Mitigation should go together with adaptation, especially in vulnerable countries like Nepal.

Climate change gases (greenhouse gases) are atmospheric gases that absorb infrared heat emitted by the Earth's surface and re-radiate it back, causing the greenhouse effect. Human activities have increased them sharply since the Industrial Revolution, causing global warming and climate change.

Mitigation measures

Mitigation means cutting GHG emissions at the source or increasing sinks that absorb them.

• Clean energy: expand hydropower, solar, wind and micro-hydro; phase down coal, oil and gas.
• Energy efficiency: LED lights, efficient motors, better building insulation, energy audits in industry.
• Clean transport: electric vehicles and electric public transport, cable cars, non-motorised transport (cycling, walking).
• Forests and land: stop deforestation, plant trees, community forestry, REDD+ (Reducing Emissions from Deforestation and Forest Degradation).
• Agriculture: less chemical fertiliser, organic farming, better manure handling, improved paddy water management.
• Waste: reduce, reuse, recycle; capture landfill methane; biogas from kitchen and animal waste.
• Industry: cleaner production, replacing old brick kilns with zig-zag kilns, low-carbon cement.
• Carbon pricing and policy: carbon tax, emissions trading, removing fossil fuel subsidies.
• Awareness and lifestyle: saving energy, less food waste, using public transport.

International efforts to tackle climate change

Key features of these efforts:

• UNFCCC (1992): framework treaty, principle of "common but differentiated responsibilities" – developed countries, which emitted most in the past, should lead.
• Kyoto Protocol (1997): first legally binding targets; developed countries to cut emissions by an average of about 5% below 1990 levels in 2008–2012. Introduced flexible mechanisms – Clean Development Mechanism (CDM), Joint Implementation and Emission Trading. Nepal's biogas programme earned carbon credits under CDM.
• Paris Agreement (2015): all countries, rich and poor, set their own Nationally Determined Contributions (NDCs), update them every five years and report progress; Global Stocktake every five years.
• Climate finance: Green Climate Fund, Adaptation Fund, Least Developed Countries Fund, and the new Loss and Damage Fund.
• Other agreements: Montreal Protocol (1987) and its Kigali Amendment (2016) phase out CFCs and HFCs.

Nepal is a party to the UNFCCC, Kyoto Protocol and Paris Agreement. It has prepared NAPA (2010), LAPA (2011), the National Climate Change Policy (2019), the National Adaptation Plan (2021) and its second NDC (2020), with a target of net-zero emissions by 2045.

Climate change is a long-term change in the average weather patterns – temperature, rainfall, wind and seasons – of a region or the whole Earth, lasting for decades or longer. The UNFCCC defines it as change attributed directly or indirectly to human activity that alters the composition of the global atmosphere, over and above natural variability.

Causes

Natural causes (minor in the present warming)

• Changes in solar output and in the Earth's orbit.
• Volcanic eruptions (dust and SO₂).
• Ocean currents such as El Niño.

Human (anthropogenic) causes (main cause today)

1. Burning fossil fuels – coal, petrol, diesel and gas for power, transport and industry release CO₂.
2. Deforestation – fewer trees absorb CO₂, and burning forests releases it.
3. Agriculture – paddy fields and livestock release methane; chemical fertilisers release N₂O.
4. Industry – cement, steel, brick kilns; halocarbons from refrigeration.
5. Waste – landfills and open dumping give methane.
6. Urbanisation and population growth – more energy demand and land-use change.

These activities raise greenhouse gases: CO₂ is now over 420 ppm compared with about 280 ppm before 1750.

Impacts

In Nepal, temperature in the mountains is rising faster than the global average, glaciers are retreating and floods and landslides are increasing.

Mitigation measures

• Clean energy: expand hydropower, solar, wind and micro-hydro; phase down coal, oil and gas.
• Energy efficiency: LED lights, efficient motors, better building insulation, energy audits in industry.
• Clean transport: electric vehicles and electric public transport, cable cars, non-motorised transport (cycling, walking).
• Forests and land: stop deforestation, plant trees, community forestry, REDD+ (Reducing Emissions from Deforestation and Forest Degradation).
• Agriculture: less chemical fertiliser, organic farming, better manure handling, improved paddy water management.
• Waste: reduce, reuse, recycle; capture landfill methane; biogas from kitchen and animal waste.
• Industry: cleaner production, replacing old brick kilns with zig-zag kilns, low-carbon cement.
• Carbon pricing and policy: carbon tax, emissions trading, removing fossil fuel subsidies.
• Awareness and lifestyle: saving energy, less food waste, using public transport.

Adaptation measures are also needed, for example GLOF early-warning systems, drought-tolerant crops, water harvesting and climate-resilient infrastructure, as planned in Nepal's NAPA and National Adaptation Plan.

Climate change is a global problem because greenhouse gases mix in the whole atmosphere, so no single country can solve it. Since the late 1980s the world has made a series of international efforts under the United Nations.

Current international efforts

Main features

• IPCC gives the scientific basis; its Sixth Assessment Report (2021–23) states that human influence has clearly warmed the climate.
• UNFCCC holds a Conference of the Parties (COP) every year and follows the principle of common but differentiated responsibilities.
• Kyoto Protocol set binding targets only for developed countries and created market mechanisms (CDM, emission trading).
• Paris Agreement is the present framework: every country submits Nationally Determined Contributions (NDCs), updated every 5 years, with a transparency framework and a Global Stocktake every 5 years. Many countries have net-zero targets (EU 2050, China 2060, India 2070, Nepal 2045).
• Climate finance: Green Climate Fund, Global Environment Facility, Adaptation Fund, Loss and Damage Fund.
• Other measures: Montreal Protocol and Kigali Amendment (halocarbons), REDD+ for forests, Global Methane Pledge (2021), carbon markets.

Are they enough?

No – the efforts are important but not enough.

1. Emissions are still rising. Global CO₂ concentration keeps rising every year (over 420 ppm), and recent years have been the hottest on record.
2. Ambition gap: UNEP Emissions Gap Reports show that even if all present NDCs are achieved, the world is heading for roughly 2.5–3 °C of warming, far above the Paris goal of 1.5 °C.
3. Voluntary pledges: NDCs under the Paris Agreement are not legally binding in their targets, and there is no penalty for missing them.
4. Finance gap: the US$100 billion per year promise was met late (2022), and developing countries say the needs are in trillions. Adaptation finance is much smaller than mitigation finance.
5. Weak participation at times: the USA never ratified Kyoto, and has left the Paris Agreement more than once; Canada left Kyoto.
6. Fossil fuel dependence: large subsidies to coal, oil and gas continue; phase-out language is weak ("phase down", "transition away").
7. Unfair burden: poor and mountain countries like Nepal, which emitted little, suffer the most, while loss and damage funding is very small.

What more is needed: stronger and binding emission cuts by major emitters, an end to fossil fuel subsidies, large and predictable finance and technology transfer to LDCs, more funding for adaptation and loss and damage, and action by individuals and businesses alongside governments.

Nepal contributes only a tiny share of global greenhouse gas emissions (about 0.03%, with per-person emissions far below the world average), yet it is ranked among the countries most vulnerable to climate change. This is a clear case of climate injustice.

Why Nepal is least responsible

• Low industrialisation; very little coal or heavy industry.
• Electricity comes almost entirely from hydropower, a renewable source.
• Per-capita energy use and vehicle ownership are low.
• About 45% of land is under forest, which acts as a carbon sink (community forestry).
• Historically, the CO₂ that is warming the world today was emitted mostly by industrialised countries since the Industrial Revolution.

Why Nepal is most affected

1. Fragile Himalayan geography: young, steep mountains prone to landslides and erosion.
2. Faster warming at altitude: temperature in Nepal's mountains is rising faster than the global average.
3. Glacier melt and GLOF risk: glaciers are retreating; lakes like Tsho Rolpa and Imja are growing.
4. Monsoon dependence: about 80% of rainfall falls in the monsoon; erratic rain causes floods (e.g. Melamchi 2021) and droughts.
5. Agriculture-based economy: most people depend on rain-fed farming, so crop failure directly hits food security.
6. Hydropower and water: changes in river flow threaten the main energy source; springs are drying in the hills.
7. Health and biodiversity: dengue and malaria spreading to the hills; species moving upward.
8. Low adaptive capacity: poverty, weak infrastructure and limited finance and technology make recovery hard.

Nepal has therefore raised the voice of mountain countries and LDCs at the UNFCCC, prepared NAPA (2010), LAPA and the National Adaptation Plan (2021), and seeks climate finance and loss-and-damage support while committing to net-zero emissions by 2045.

Climate change is the long-term change in the average weather pattern (temperature, rainfall, seasons) of the Earth or a region, mainly due to an increase of greenhouse gases from human activity, which causes global warming.

Causes

• Burning fossil fuels (coal, oil, gas) in power plants, vehicles and industries – main source of CO₂.
• Deforestation and land-use change – fewer trees to absorb CO₂.
• Agriculture – methane from paddy and livestock; N₂O from fertilisers.
• Industry and waste – cement, brick kilns, halocarbons (CFCs/HFCs), methane from landfills.
• Population growth and urbanisation – increasing energy demand.
• Natural factors (solar changes, volcanoes, El Niño) play a smaller role.

Impacts

• Global temperature rise (about 1.1–1.2 °C so far) and heat waves.
• Glacier melt, glacial lake outburst floods (GLOF), sea level rise.
• Erratic rainfall: floods, landslides and droughts.
• Lower crop yield, food and water scarcity.
• Spread of diseases like malaria and dengue.
• Loss of biodiversity and damage to infrastructure.

Feasible solutions for Least Developed Countries (LDCs)

LDCs emit little, so their priority is adaptation plus low-cost, co-beneficial mitigation that also supports development.

1. Renewable energy: develop hydropower, micro-hydro, solar home systems, improved cooking stoves and biogas instead of firewood and imported fuel.
2. Community forest management and REDD+: protect and expand forests, earn carbon finance.
3. Climate-smart agriculture: drought- and flood-tolerant seeds, crop diversification, organic farming, small irrigation and rainwater harvesting.
4. Disaster risk reduction: GLOF early warning, flood forecasting, safe building codes, landslide mapping.
5. Local adaptation plans: community-based adaptation (e.g. Nepal's NAPA 2010 and LAPA) that involve local people.
6. Water management: spring-shed protection, recharge ponds, efficient use.
7. Clean transport: electric vehicles and public transport using domestic hydropower.
8. Access to international support: Green Climate Fund, Adaptation Fund, LDC Fund, Loss and Damage Fund; technology transfer and capacity building under the UNFCCC and Paris Agreement.
9. Awareness and education: include climate change in school curricula and local planning.
10. Strong policy and institutions: integrate climate change into national plans and budgets (climate budget coding).

These solutions are feasible because they are cheap, use local resources and labour, and give direct benefits such as jobs, clean air and energy security, while reducing vulnerability.