Black carbon and melting of glaciers
- September 29, 2022
- Posted by: OptimizeIAS Team
- Category: DPN Topics
Black carbon and melting of glaciers
Subject: Environment
Context:The glaciers in the western Himalayas, source of water for Jammu, Kashmir and Ladakh, have been melting at a significant rate due to the growing amount of black carbon aerosol and greenhouse gases, which is leading to the darkening of the region’s snowpack, researchers have found in various studies.
Details:
- In a recent study, around 77 glaciers in the Drass basin of the Ladakh region were evaluated using satellite data. The study was used to investigate the shrinkage, snout retreat, ice thickness changes, mass loss and velocity changes of these glaciers between 2000 to 2020.
- The findings indicated that glaciers in the Drass region have thinned by 1.27 metres between 2000-2020. Besides soaring regional temperatures, research indicates that the region’s black carbon (or soot, a component of particulates) increased from 330 nanograms to 680 nanograms from 1984-2020.
- The study tried to establish a link between greenhouse gases, black carbon and increased glacial melt in the Himalayas.
- Black carbon deposition on glaciers decreases the reflectivity of ice surface resulting in faster ice melt. Likewise, increasing black carbon concentration in the atmosphere, increases radiative forcing and upon deposition on glaciers absorbs solar radiation, ultimately playing a part in fast-melting of snow cover and glaciers in the mountain.
Albedo Effect:
- Albedo is an expression of the ability of surfaces to reflect sunlight (heat from the sun). Light-coloured surfaces return a large part of the sunrays back to the atmosphere (high albedo). Dark surfaces absorb the rays from the sun (low albedo).
- Ice- and snow-covered areas have high albedo, and an ice-covered Arcticreflects solar radiation which otherwise would be absorbed by the oceans and cause the Earth’s surface to heat up. The proportion of the Earth’s surface that is covered by snow and ice has a great deal to say for how much of the incoming solar radiation is reflected or absorbed. Low albedo (dark surfaces) leads to higher uptake of energy and, hence, warming. Moreover, when more ice and snow melt, there will be more dark surfaces. This is therefore a self-reinforcing effect. Climate change in the Arctic is consequently important for the development of climate change globally.
Main Reason of Black carbon
In Kashmir, a major factor for the increase in black carbon is the burning of pruned branches of orchard trees in autumn and woody biomass for heating in winter mainly driven by economic considerations as the horticulture sector gives 5-6 times more monetary benefits to farmers than paddy cultivation
Long Term Consequence
- It will affect the downstream community in the Indus basin, which encompasses the Union Territory of Jammu and Kashmir, states Himachal Pradesh, Punjab and a part of Rajasthan, Haryana, and Union Territory of Chandigarh, having an area of 3,21,289 sq. km., nearly 8% of the total geographical area of the country.
- The Indus is the westernmost river system in the subcontinent. Jhelum,Chenab, Ravi, Beas and Satluj are its main tributaries.
- There are more than 12000 glaciers in the Jammu, Kashmir and Ladakh region, which forms the Upper Indus Basin (UIB). The melt waters, emanating from these glaciers in the UIB meet about 80% water demands of neighbouring Pakistan. Therefore, the melting glaciers, if the causes are not understood in the right perspective, might affect the security situation in South Asia because of the transboundary nature of the rivers
About Black Carbon:
- BC is a short-lived pollutant that is the second-largest contributor to warming the planet behind carbon dioxide (CO2). Black carbon is a kind of an aerosol. An aerosol is a suspension of fine solid particles or liquid droplets in the air.
- Black carbon is commonly known as soot. Soot is a form of particulate air pollutant, produced from incomplete combustion.
- India and China are the largest emitters of black carbon in the world.
- It gets emitted from gas and diesel engines, coal-fired power plants, and other sources that burn fossil fuel. It comprises a significant portion of particulate matter or PM2.5, which is an air pollutant.
- Unlike other greenhouse gas emissions, BC is quickly washed out and can be eliminated from the atmosphere if emissions stop.
- Unlike historical carbon emissions it is also a localised source with greater local impact.
- It emits infra-red radiation that increases the temperature.
- Black carbon has a warming impact on climate 460-1,500 times stronger than CO2 per unit of mass
- The average atmospheric lifetime of black carbon particles is 4-12 days
Climate and Clean Air Coalition (CCAC):
- The Climate and Clean Air Coalition is a voluntary partnership of governments, intergovernmental organizations, businesses, scientific institutions and civil society organizations committed to improving air quality and protecting the climate through actions to reduce short-lived climate pollutants which includes Methane, black carbon and hydrofluorocarbons (HFCs) etc.
What are short-lived climate pollutants?
- Short-lived climate pollutants are those pollutants which are short lived in the atmosphere.
- They are also known as Super Pollutants.
- Methane, black carbon and hydrofluorocarbons (HFCs) are some examples of short-lived pollutants.
- They are many times more powerful than carbon dioxide at warming the planet.
- But because they are short-lived in the atmosphere, preventing emissions can rapidly reduce the rate of warming.
Way forward measures to reduce Black Carbon:
- To electrify transportation in urban areas
- Replace coal with renewable
- Upgrade vehicles to the latest auto emission norms (Bharat Stage VI)
- Switch to clean cooking fuels and cleaner brick production technologies
- Enacting new policies later on and incorporating them through regional cooperation among states and neighboring countries (i.e., Nepal, Bhutan, Bangladesh, and Pakistan) can achieve enhanced benefits