Rising evaporative demand spotlights India’s
data and research gap

Notes for Students
Topic: Rising Evaporative Demand and India’s Data-Research Gaps, Source: The Hindu article by G.B.S.N.P. Varma, referencing recent research (Earth’s Future, March 2025)
Context of the Article: India lacks research and monitoring infrastructure to track increasing atmospheric thirst (evaporative demand), especially as global warming intensifies thirst waves — prolonged periods of high evaporative stress affecting agriculture and water use.
UPSC Paper Relevance: GS1 (Geography), GS3 (Environment, Agriculture, Disaster Management, Climate Change)
Dimensions of the Article:
- Policy and research gaps in climate adaptation for Global South
- Climate change-induced thirstwaves intensifying agricultural stress
- Lack of data on India’s regional evapotranspiration and humidity effects
- Evaporative demand as critical input for irrigation, crop water use
Current context
- Global Warning Signal: New research in Earth’s Future (Kukal & Hobbins, 2025) highlights “thirstwaves” — periods of 3+ days with high evaporative demand — as growing in frequency, duration, and intensity, especially during crop seasons in the U.S.
- India’s Blind Spot: Despite similar vulnerabilities, India has no structured data or research on extreme thirstwaves, especially across its varied agro-climatic zones.
- Importance for India: Agricultural output, food security, and water use efficiency are at stake. Standard tools to measure evapotranspiration are underutilized. Current irrigation planning doesn’t account for rising atmospheric demand.
- Future Work: Ongoing Indo-US research (Kukal & Sharma, NIT Jalandhar) aims to explore thirstwave behaviour in South Asia, with global implications for climate-resilient food and water systems.
Features of the News
1. What is Evaporative Demand?
- Definition: It refers to how “thirsty” the atmosphere is — how much water it can pull from land and vegetation if water is available.
- Key Factor: It is determined by temperature, wind speed, humidity, and solar radiation.
- Measurement Tool: Standardised Short-Crop Evapotranspiration (ET₀), based on a 12-cm high grass model with unlimited water — isolates weather from vegetation differences.
2. What are Thirstwaves?
- Coined By: Meetpal Kukal & Mike Hobbins.
- Defined As: 3+ consecutive days of high evaporative demand.
- Distinct From Heatwaves: Not just high temperature — include humidity, radiation, wind.
- Trend (U.S.): More severe, frequent, and longer thirstwaves. Low chance of growing seasons without them now.
3. India’s Current Research Gaps
- Old Studies: 1997 paper by Chattopadhyay & Hulme found evaporation decreasing over 30 years in India — contrary to global warming logic.
- Explanation: Humidity increases offset temperature effects in the past. Future warming may override this.
- Recent Studies (2022): IIT-Roorkee et al. found increases in evapotranspiration in 100 sub-basins — especially Northern India, Western and Eastern Himalayas.
- Missing Data: No tracking of extreme thirstwave events or their spatial-temporal impact on Indian crops, soils, and water regimes.

4. Climate Risk for Indian Agriculture
- Crop Water Needs: Evaporative demand dictates how much water crops like wheat or rice will transpire even with sufficient irrigation.
- Increased Demand = Increased Irrigation: Without accounting for this, irrigation efficiency and water budgeting suffer.
- Need for Integration: Irrigation planning must integrate daily/seasonal evaporative demand — not just static or average metrics.
5. International Research Efforts
- South Asia Focus: Kukal is currently guiding research with Indian scholars (e.g., Shailza Sharma) under a global water innovation grant.
- Goal: Map thirstwaves in India and climate-vulnerable regions of Global South.
- Key Insight: Some worst thirstwaves don’t occur in hottest regions — pointing to misprioritization in national climate planning
Measured By – Standardised Short-Crop Evapotranspiration (ET₀)
Definition:
A simplified metric used to quantify evaporative demand, based on a reference grass crop under ideal conditions.
Explanation:
It assumes:
- A 12 cm tall grass with no water stress.
- Weather (temperature, humidity, wind, radiation) is the only influencing factor.
This becomes a standard reference to help estimate how much water crops would lose to the atmosphere, and is used in irrigation scheduling and climate studies.
Thirstwave
Definition:
A newly defined climate phenomenon — 3 or more consecutive days of abnormally high evaporative demand.
Explanation:
Coined by researchers Kukal and Hobbins (2025), this is a composite stress event affecting land, crops, and ecosystems due to heightened atmospheric water demand. It is comparable to a heatwave but has different causative factors.
Difference from Heatwave
Definition:
A heatwave is primarily driven by temperature, whereas a thirstwave is driven by multiple weather variables.
Explanation:
A thirstwave includes:
- High temperature
- Low humidity
- Strong winds
- High solar radiation
While a heatwave directly impacts human health, a thirstwave has more pronounced impacts on water loss, agriculture, and vegetation stress.
Findings in the U.S.
Observation:
Research shows that thirstwaves are becoming more frequent, longer, and more intense in the U.S., especially during growing seasons.
Explanation:
There is now a very low probability that agricultural growing periods will not experience a thirstwave. This indicates a shift in baseline climate and growing conditions, even in technologically advanced agricultural systems.
Findings in India
Historical (1997 Study):
- Evapotranspiration decreased despite warming, due to counteracting effect of increased humidity.
Recent (2022 Study):
- Increase in evapotranspiration in Northern India and Himalayan regions — possibly due to agricultural expansion and vegetation increase.
Explanation:
India’s changing climatic patterns and land-use changes are now likely amplifying evaporative demand, but national-level data lacks granularity on extreme events like thirstwaves.
Current Gap
Definition:
There is no comprehensive dataset or study on extreme thirstwave events across Indian regions.
Explanation:
Despite India being highly vulnerable (due to monsoon dependency, irrigation challenges, crop season sensitivity), there is no dedicated monitoring or classification of thirstwaves — unlike heatwaves. This limits adaptive response.
Implications
Key Risks:
- Crop Stress: Crops use more water, risk wilting or yield loss.
- Irrigation Efficiency: Higher demand not factored into irrigation planning.
- Disaster Unpreparedness: No early warning for prolonged high evaporative demand.
Explanation:
Thirstwaves affect both rainfed and irrigated agriculture. They also stress forest systems and water bodies, pushing up energy and water use for irrigation. Unpreparedness can lead to food and water security risks.
Research Ongoing
Ongoing Work:
- Meetpal Kukal and Indian scholar Shailza Sharma (NIT Jalandhar) are studying thirstwaves in South Asia under a global water research initiative.
Explanation:
This Indo-U.S. research aims to provide first-of-its-kind data on the frequency, location, and intensity of thirstwaves in India and neighbouring regions — with significant implications for climate-resilient agriculture.
Policy Need
Urgent Recommendation:
- Integrate evaporative demand into:
- Irrigation planning
- Agricultural advisories
- Climate disaster preparedness
Explanation:
Current policies use rainfall and temperature but ignore evaporative demand, which is equally (or more) important in deciding crop water needs. Regions may be misclassified for climate risk if evaporative demand is not considered. Including this parameter will improve accuracy in climate impact mapping and water allocation.
Pakistan’s role in the U.S.-West Asia calculus

Notes for Students
Topic: Pakistan’s Role in the U.S.–West Asia Calculus, Source of News: The Hindu – World Insight by D.P. Srivastava
Context of Article: U.S. airstrikes on Iranian nuclear sites and Pakistan’s strategic engagement with the U.S. amidst growing regional instability involving Iran, Israel, and Afghanistan
UPSC Paper Relevance: GS Paper II – International Relations
Dimensions of the Article:
- West Asia’s conflict linkages with South Asia
- Strategic realignment of Pakistan with the U.S.
- Pakistan’s Iran contradictions and border politics
- Sectarian conflicts and domestic instability
Current Context
On June 22, 2025, U.S. President Donald Trump launched military strikes on Iranian nuclear facilities, marking a major escalation in West Asia. Prior to this, Pakistan’s Army Chief, General Munir, held a high-profile meeting with Trump — raising questions about Pakistan’s new strategic posturing. This development unfolds amid U.S. concerns over Israel’s security and Iran’s regional influence. With Pakistan closing its borders with Iran and securing new IMF support, its role as a U.S. ally in containing Iran is gaining importance. Simultaneously, Pakistan’s domestic contradictions — sectarian tensions, Baloch unrest, and economic crisis — reveal the instability underlying its external alignment.
Features of the News

1. U.S. Airstrikes and the Iran Conflict
- U.S. conducted attacks on three Iranian nuclear sites on June 22.
- Trump threatened “far greater” attacks if Iran resists.
- Iranian FM Abbas Araqchi vowed all options to defend sovereignty.
- Previous similar interventions in Iraq and Libya caused long-term destabilisation.
2. Pakistan-U.S. Alignment and Military Diplomacy
- General Munir’s June 18 meeting with Trump broke protocol norms.
- It followed Israeli attacks on Iran (June 13) and hinted at U.S.-Pakistan collusion.
- CENTCOM chief praised Pakistan in Senate hearing for counter-terror operations — citing extradition of Mohammad Sharifullah (accused in Kabul airport bombing, 2021).
- Despite past duplicity in Afghanistan, Pakistan is now again positioned as a U.S. partner.
3. Pakistan-Iran Complexities and Border Moves
- Competition over Afghanistan influence.
- 2024 missile exchanges over insurgent attacks.
- Pakistan closed land borders with Iran (June 15) except for nationals’ return.
- Iran depends on land trade routes for food imports — closure can squeeze Iran during port shutdowns in Persian Gulf.
- Smuggling and electricity cooperation (e.g., Gwadar power supply) still exist.
4. Economic Leverage and IMF Support
- Pakistan got $1.4 billion under IMF climate resilience plan and $1 billion under previous commitments, amid its military budget rise and India-Pak conflict.
- Total defence budget for FY 2025–26: PKR 3.29 trillion ($11.65 billion) — up 17%.
- Military pensions excluded in official defence budget.
- Development sector slashed by 50%.
- Interest payment (PKR 8.2 trillion) forms 74% of federal revenue — more than total defence and debt service allocation.
- Forex reserves at $11.5 billion made possible by rollover of $16 billion loans from friendly countries.
5. Ideological and Sectarian Politics
- General Munir’s April 16 speech invoked “superior ideology” and Pakistan’s two-nation theory.
- He reaffirmed claim on Kashmir and highlighted ideological purity over ethnic pluralism.
- Balochistan conflict linked to forced accession in 1947 (Khan of Kalat’s independence nullified by military action).
- Baloch nationalism targeted using Sunni extremist groups supported by Pakistani military.
- These groups also attack Shia pilgrims heading to Iran — widening sectarian rift with Iran.
- Gwadar (Balochistan) used as a Chinese naval outpost, not for trade (just 1% of Pakistan’s maritime activity).
6. Strategic Implications and Contradictions
- Pakistan could act as a strategic land block if Persian Gulf ports are shut in wartime.
- General Munir’s anti-Israel and pro-Gaza posturing conflicts with U.S. alignment — a balancing act to appease domestic Islamist forces.
- This contradiction — supporting jihadist constituencies while aligning with the U.S. a gainst Iran — shows Pakistan’s double-edged diplomacy.
- While aiming to gain strategic and economic support from the U.S., Pakistan risks internal backlash from radical groups it has long supported.

Explainer
1. U.S. Airstrikes on Iran
Definition:
On June 22, 2025, the U.S. launched targeted military strikes on three Iranian nuclear sites.
Explanation:
This marks a major escalation in the ongoing Iran-Israel-West conflict. It risks igniting a larger regional war. The strikes come amid U.S. strategic recalibration and rising tension in the Persian Gulf. Iran has vowed retaliation, making it a potential long-term conflict akin to Iraq or Libya post-intervention.
2. Thrust of U.S.-Pakistan Military Diplomacy
Definition:
Unprecedented engagement between U.S. President Trump and Pakistan’s Army Chief General Asim Munir, including a private White House meeting.
Explanation:
Normally reserved for heads of state, this meeting signals a renewed U.S.-Pakistan strategic partnership, not for South Asia (India-Pakistan), but to serve U.S. interests in West Asia, especially in countering Iran. CENTCOM praises Pakistan for counter-terror actions, indicating trust restoration.
3. Pakistan-Iran Bilateral Complexity
Definition:
A geopolitical relationship marked by cooperation and competition, particularly over Afghanistan and border security.
Explanation:
Pakistan’s Sunni-majority ideology and strategic ties with Saudi Arabia contrast with Shia-majority Iran’s regional ambitions. There are border tensions (including 2024 missile exchanges) and covert support to anti-Iran groups by Pakistan, leading to mistrust. Yet, trade, energy, and geography bind them.
4. Border Closure and Land Trade Route Disruption
Definition:
Pakistan’s unilateral decision on June 15, 2025 to close land borders with Iran during peak regional conflict.
Explanation:
Iran’s dependency on overland trade — particularly for food and essentials — makes this move significant. It indicates Pakistan aligning more closely with U.S.-Israel interests. Smuggling of fuel and cross-border exchanges still exist, but formal trade links are frozen, increasing Iran’s isolation.
5. IMF Support and Economic Leverage
Definition:
Pakistan received $1.4 billion under the IMF climate program and another $1 billion from previous bailout tranches.
Explanation:
Amid economic collapse and military aggression towards India, Pakistan secured U.S.-facilitated aid. The IMF funds serve as diplomatic carrots to ensure Pakistan’s cooperation against Iran. It’s a classic case of economic aid being used as a geostrategic instrument.
6. Pakistan’s Rising Defence Budget
Definition:
FY 2025–26 saw a 17% increase in Pakistan’s defence budget, with total military expenditure crossing PKR 3.29 trillion.
Explanation:
Despite economic distress, Pakistan prioritises defence over development. Military pensions are kept separate to obscure the true size. Development outlay shrinks by 50%. Most of Pakistan’s revenue now services debt and defence, making governance dependent on loans.
7. Sectarian and Ideological Divide with Iran
Definition:
Religious fault lines between Sunni-majority Pakistan and Shia-majority Iran, worsened by military-supported Sunni extremist groups in Pakistan.
Explanation:
Pakistan’s support to Sunni jihadist outfits serves two purposes:
- Countering Baloch separatism (internally)
- Weakening Iran’s regional appeal (externally)
However, this worsens sectarian violence — including attacks on Shia pilgrims en route to Iran — and undermines diplomatic ties with Tehran.
8. Strategic Geography: Balochistan’s Role

Definition:
Pakistan’s Balochistan province borders Iran’s Sistan-Balochistan — a region critical for Chabahar and Gwadar ports.
Explanation:
While Chabahar (Iran) is India-supported and civilian, Gwadar (Pakistan) is Chinese-backed and military-focused. Balochistan remains volatile due to separatism, repression, and ideology-based policies. Control of this region is strategically vital for regional power projection by China and the U.S.
9. Pakistan’s Internal Contradictions
Definition:
Despite siding with the U.S. against Iran, Pakistan publicly supports Gaza and condemns Israel.
Explanation:
This dual messaging is aimed at managing domestic Islamist narratives while retaining U.S. strategic favour. It reflects Pakistan’s long-standing practice of ideological duality — catering to jihadist groups at home while seeking Western aid and military partnership abroad.
10. Ideology as a Political Instrument
Definition:
General Munir’s invocation of the “superior ideology” and the two-nation theory to justify Kashmir claim and suppress ethnic dissent.
Explanation:
This ideological thrust rejects internal diversity (e.g., Baloch identity) in favour of Islamic uniformity. Historically, this has alienated peripheral regions like Balochistan. Munir’s ideological rhetoric aims to consolidate national identity through militarised religion, but fuels internal unrest.
Polls and processes

Notes for Students
Topic: By-elections and Electoral Process Integrity in India
Source of News: The Hindu Editorial – “Polls and processes”
Context of the Article: Recent by-election results in five Assembly constituencies and the proactive transparency measures by the Election Commission of India (ECI)
UPSC Paper Relevance: GS Paper II – Governance and Polity
Dimensions of the Article:
- Election Commission’s reforms and transparency initiatives
- Electoral outcomes and regional political trends
- Shifting party dynamics in states like Kerala, Punjab, Gujarat, and West Bengal
- Electoral violence and democratic credibility
Current Context
The results of by-elections in five Assembly constituencies — Kadi (Gujarat), Visavadar (Gujarat), Nilambur (Kerala), Ludhiana West (Punjab), and Kaliganj (West Bengal) — highlight local political shifts and the Election Commission of India’s (ECI) efforts to enhance transparency and trust in the electoral process. These elections were crucial as state assembly polls in Kerala and West Bengal are due next year, and each result reflects ground-level party strengths, internal defections, candidate dynamics, and voter response. Simultaneously, the ECI introduced notable reforms to improve process integrity amid continuing challenges like violence and allegations of last-hour booth rigging.
Features and Factual Insights from the News
1. Nilambur (Kerala) – Congress Gains, AAP & BJP Lose Ground
- Winner: Aryadan Shoukath (Congress-led United Democratic Front).
- The seat became vacant after P.V. Anvar (Left-backed independent) resigned following a rift with the ruling coalition.
- Anvar unsuccessfully tried to contest as a TMC candidate, then stood as an independent.
- Nilambur is part of the Wayanad Lok Sabha constituency, currently held by Priyanka Gandhi (Congress).
- The BJP performed poorly, showing weak presence in the region.
- Outcome is expected to impact campaign strategies for 2026 Kerala Assembly elections, altering communal alignment and party strength dynamics.
2. Kaliganj (West Bengal) – TMC Victory, Marred by Violence
- Winner: Alifa Ahmed (TMC), won by over 50,000 votes.
- Seat was vacated due to the death of her father, a former MLA.
- Counting day witnessed a child’s death in a crude bomb explosion, reflecting persistent electoral violence in West Bengal.
- The result reinforces TMC’s strength, but raises concerns about democratic safety and peaceful polling in the state’s volatile environment.
3. Visavadar (Gujarat) – AAP’s Symbolic Comeback
- Winner: Gopal Italia (AAP), former Gujarat State President.
- The seat was earlier held by an AAP MLA who defected to BJP.
- The win helps AAP retain political footing in Gujarat, despite earlier setbacks and loss in Delhi elections (Feb 2025).
- Reflects voter pushback against defection and renewed mandate for AAP in the state.
4. Ludhiana West (Punjab) – AAP Consolidates
- Winner: Sanjeev Arora (AAP), industrialist and former Rajya Sabha MP.
- Punjab is already governed by AAP, and this win shows continued voter trust in its urban leadership.
- AAP remains relevant and stable in Punjab’s political landscape post-national election losses.
5. Kadi (Gujarat) – BJP Holds Fort
- Winner: BJP retained the seat.
- Shows BJP’s pocket hold and consistent base in certain Gujarat constituencies.
- Not a major shift, but contributes to BJP’s overall state presence.
6. Election Commission of India (ECI) – Transparency Reforms
Proactive measures introduced in these by-elections:
- Mobile deposit facility at all polling stations — reducing voter movement issues.
- Faster sharing of voter turnout data — improves media access and public trust.
- Webcasting at 100% polling stations — visual monitoring for accountability and post-poll review.
Challenges still present:
- Disputes over high last-hour polling in sensitive booths remain unresolved.
- Transparency issues related to access and release of booth videos.
- ECI is under pressure to not only ensure fairness but also public perception of fairness.
Conclusion:
These by-elections act as a barometer for state-level political shifts, offer insight into voter sentiments post-Lok Sabha elections, and test the ECI’s capacity to deliver transparent and peaceful elections. The editorial calls for continued vigilance and reform to safeguard India’s democratic integrity, especially in politically volatile or violence-prone regions like West Bengal.
Many Images

Notes for Students
Topic: Symbolism, Federalism, and Political Neutrality in Constitutional Offices
Source of News: The Hindu Editorial – “Many images”
Context of the Article: Recent controversy in Kerala over the Governor displaying a saffron-flag-holding Bharat Mata image with Akhand Bharat map at Raj Bhavan events, triggering protests from state ministers and political unrest
UPSC Paper Relevance: GS Paper II – Polity and Governance (Federalism, Role of Governors, Political Ethics)
Dimensions of the Article :
- Political weaponisation of historical imagery
- Symbolism and ideological messaging from constitutional positions
- Clash between cultural iconography and secular state principles
- Tensions between Governor and State Government
Current Context
Kerala Governor Rajendra Vishwanath Arlekar’s decision to display a portrait of Bharat Mata holding a saffron flag in front of a lion and Akhand Bharat map during official Raj Bhavan events has provoked a political backlash. Two Kerala ministers boycotted functions in protest, claiming it reflected Hindu nationalist symbolism inappropriate for a constitutional post. The issue has intensified tensions between the Left Democratic Front (LDF) government and the Governor, with street-level clashes erupting between CPI(M) and BJP workers. The editorial argues that Governors must maintain ideological neutrality, particularly in a diverse, secular democracy like India.
Feature Breakdown and Factual Expansion
1. The Controversial Imagery
- The Governor displayed a garlanded portrait of Bharat Mata, shown:
- Holding a saffron flag
- Standing in front of a lion
- With a background map resembling Akhand Bharat (undivided India concept)
- Left Democratic Front leaders condemned it as an attempt to Hinduise the constitutional space.
- Governor defended the act as a reflection of nationalism and patriotism, not religious propaganda.
2. Immediate Political Fallout
- Two state ministers publicly boycotted official Raj Bhavan functions in protest.
- The controversy spilled into the streets, triggering:
- Protests and counter-protests
- Clashes between CPI(M) and BJP cadres
- The move shattered the initial harmony Governor Arlekar had maintained with the State Government during his early tenure.
3. Historical Evolution of the Bharat Mata Image
- Origin: From Bankim Chandra Chattopadhyay’s novel Anandamath (late 19th century).
- Portrayed Bharat Mata as a Hindu goddess, victimised and in need of revival.
- Introduced “Vande Mataram”, later India’s national song.
- Criticised for communal overtones, especially its Hindu-only lens.
- Abanindranath Tagore’s version (early 20th century):
- Depicted Bharat Mata as a four-armed woman, holding:
- White cloth
- Book
- Beads
- Sheaves of paddy
- Seen as more inclusive, representing spiritual and cultural India.
- Depicted Bharat Mata as a four-armed woman, holding:
- Other artistic interpretations:
- Amrita Sher-Gil: Depicted Bharat Mata as a suffering, uncertain mother.
- Satyajit Ray’s film Devi: Critiqued the deification of women as a patriarchal tool.
- M.F. Husain and other secularists: Also explored nation-as-woman imagery, often in non-sectarian ways.
4. Cultural and Political Instrumentalisation
- Over time, religious nationalists weaponised the Bharat Mata motif:
- Merged it with Hindu Rashtra ideals.
- Promoted the idea of Akhand Bharat, blending myth, nationalism, and majoritarian identity.
- Flag usage (saffron vs tricolour) reflects ideological leaning.
- The image became ubiquitous in calendar art, films, public culture.
- Mother India (film): Cemented the nurturer-protector stereotype.
- Used both to unify and divide, depending on the portrayal and political context.
Conclusion & Editorial Standpoint
- Bharat Mata is a multilayered symbol — artistic, spiritual, political — with no uniform depiction.
- Given this ambiguity and strong Hindu iconographic roots, its use in official state functions by constitutional authorities like Governors becomes deeply problematic.
- The editorial asserts that Governors must avoid partisan symbolism and safeguard the secular, inclusive character of the Indian State.