UPSC Prelims S.E.E. Snapshot: SAF, Economic Integration, and Breached Planetary Boundaries

SCIENCE

Sustainable Aviation Fuel

Core Concept: 

— SAF, also known as aviation biofuel, is a biofuel that is produced from sustainable feedstocks and has chemistry similar to conventional aviation turbine fuel or jet fuel, which is derived from crude oil. 

— It is a ‘drop in’ fuel, meaning it can be blended with ATF without requiring any change in the existing machinery of aircraft.

— SAF can be derived from a range of materials, including:

• Oils and fats such as Used Cooking Oil (UCO), oil-rich seeds from plants, algae oils, animal fats,

• Municipal Solid Waste (MSW)

• Agricultural and forestry residues such as wood waste, sugarcane bagasse, corn stover, husks and straw, sugars and starches.

(Image generated using Google NotebookLM)

— There are various methods to produce SAF, with each using different combinations of raw materials. 

📍UPSC Twist Points– SAF vs Hydrogen Fuel Cells

— As India accelerates its transition to sustainable transportation, major players across sectors are embracing green hydrogen mobility. 

— Hydrogen Fuel Cells (HFCs) generate high-quality electric power that is clean, quiet, and consistently reliable by converting the chemical energy stored in Hydrogen into electrical energy.

— The primary components of an HFC are the Membrane Electrode Assembly (MEA) and the bipolar plates. 

(Image generated using Google NotebookLM))

ECONOMY

Levels of Economic Integration

Core Concept: 

— Economic integration refers to the process of harmonising economic policies and activities among different member countries. It is aimed to foster closer economic cooperation and greater collaboration. 

— Economic integration typically occurs in stages. The most commonly recognised levels of economic integration are: 

(i) Preferential Trade Agreement (PTA): At this initial stage, countries agree to reduce tariffs and trade barriers on selected goods and services, when trading with each other. 

(ii) Free Trade Area (FTA): In a free trade area, participating countries eliminate or substantially reduce tariffs and trade barriers on a broad range of goods and services traded amongst them. However, each country maintains its own external trade policies and can negotiate independent agreements with non-member countries.

(iii) Customs Union: A customs union involves the elimination of internal tariffs and trade barriers among member countries and the adoption of a standard external trade policy. Member countries coordinate their trade policies and present a unified front to non-members. 

(Image generated using AI)

(iv) Common Market: A common market takes integration a step further by not only removing barriers to the movement of goods and services but also allowing for the free movement of factors of production, such as labour and capital, across borders. 

(v) Economic and Monetary Union (EMU): In EMU, there is deep integration involving harmonisation of various economic policies, and often a common currency and unified monetary policy.

(vi) Complete Economic Integration: At the highest level of economic integration, countries fully harmonise their economic policies, institutions, and regulations. This stage often involves significant political integration and the creation of supranational bodies with authority extending over member states as well. 

📍UPSC Twist Points– Customs Union vs Common Market 

— Customs Union: Elimination of internal tariffs with a common external tariff, but no free movement of labour and capital.

— Common Market: Includes a customs union and additionally ensures free movement of goods, services, labour, and capital.

ENVIRONMENT

Breached Planetary Boundaries

Core Concept: 

— Planet boundaries are a framework that identifies guardrails for humanity’s impacts on the Earth system. Put simply, it sets limits on how much humans can be allowed to impact not only the climate but also other global processes that are essential for maintaining conditions on the planet to support modern civilisations. 

— Developed in 2009, the framework includes nine planet boundaries that scientists believe capture all of the processes critical for maintaining the Earth’s system state. 

— These boundaries and their control variables are:

1. Biosphere integrity: The health of ecosystems and rate of extinction of species.

2. Climate change: Atmospheric CO2 concentration and the change in radiative forcing — a measure of the balance of energy from sunlight that hits Earth, in comparison with thermal energy the planet loses.

3. Novel entities: Levels of plastic, concrete, synthetic chemicals, gene-modified organisms, etc., that would not be found on Earth if we humans were not here.

4. Stratospheric ozone depletion: The anthropogenic release of manufactured chemicals that destroy ozone molecules.

5. Freshwater change: It includes an examination of the human-induced impact on blue water (found in lakes, rivers, and reservoirs) and green water (available in the soil for plants and soil microorganisms)

6. Atmospheric aerosol loading: Tracking various particles from anthropogenic emissions that affect cloud formation as well as global and regional atmospheric circulation.

7. Ocean acidification: Reduction in the pH of the ocean over an extended period of time.

8. Land system change: Changes in land use, especially the conversion of tropical forests to farmland.

9. Biogeochemical flow: Alteration in the natural flows and the forms of nitrogen and phosphorus cycles, which are essential elements for plant growth.

— The seven breached planetary boundaries are: Climate Change, Biosphere Integrity, Land System Change, Freshwater Use, Biogeochemical Flows, Novel Entities, and Ocean Acidification (new in 2025). All of these seven boundaries show worsening trends. Only Ozone Depletion and Aerosol Loading remain in the safe zone.

📍UPSC Twist Points– Ocean Acidification vs Climate Change

—  Ocean Acidification: The dissolving Carbon Dioxide in seawater forms carbonic acid, decreasing the ocean’s pH. This process is collectively known as ocean acidification.  

—  Climate Change: According to the Intergovernmental Panel for Climate Change (IPCC), “Climate change refers to a change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer.” 

— Notably, ocean acidification and climate change are two separate planetary boundaries. 

Prelims Practice MCQ

Let’s see how much can you recall

Consider the following statements:

1. Sustainable Aviation Fuel can be used in existing aircraft engines without requiring major modifications, as it is a drop-in fuel.

2. In a Customs Union, member countries allow free movement of labour and capital among themselves.

3. Ocean acidification is part of climate change boundary

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 1 only

(c) 2 only

(d) 1, 2 and 3

ALSO CHECK

UPSC Prelims S.E.E. Snapshot: Dimethyl Ether, CPI overhaul, Tar Balls 

UPSC Prelims ‘SEE’ Snapshot : Induction cooktop, Forex reserve, and Earth’s energy imbalance 

UPSC Prelims ‘SEE’ Snapshot: Talking cars, GDP rebasing and Nor’westers — quick look 

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