Welcome to Carbon Brief’s DeBriefed.
An essential guide to the week’s key developments relating to climate change.

This week

War and oil

HISTORIC: Leaders from 32 countries agreed to the “biggest emergency oil release in history” in response to the energy crisis sparked by the Iran war, reported Politico. The coordinated release of 400m barrels of oil by member nations of the International Energy Agency (IEA) is “more than twice” the amount released following Russia’s invasion of Ukraine in 2022, the outlet continued.

$100 BARREL: The agreement came as oil surged past $100 a barrel for the first time in four years on Monday, as “traders bet widening conflict in the Middle East would lead to weeks-long supply disruptions”, said the Financial Times. According to a report from the US Energy Information Administration, crude oil prices are likely to remain above $95 a barrel in the next two months, before falling to around $70 by the end of this year, reported Reuters. Research consultancy Wood Mackenzie, meanwhile, said oil prices could yet reach $150 per barrel, according to Reuters. 

KREMLIN: The war in Iran has pushed up demand for Russian oil and gas, with the nation making €6bn (£5bn) in fossil-fuel sales in the last fortnight, according to analysis by the Centre for Research on Energy and Clean Air covered by the Guardian. Read Carbon Brief’s Q&A on what the war means for the energy transition and climate action.

Around the world

• FLOODS: A month’s worth of rain in 24 hours triggered floods that killed more than 40 people in Kenya, reported the country’s Daily Nation newspaper. 
• NET-ZERO: A new report from the UK’s Climate Change Committee outlined that achieving net-zero by 2050 will have less of a financial impact than the kind of fossil-fuel price rises experienced during the 2022 energy crisis, reported Carbon Brief.
• SOLAR: The amount of solar energy installed in the US fell by 14% between 2024 and 2025, according to an industry report, reported the New York Times.
• WATCHING: A Paris Agreement “watchdog” will discuss this month how to respond to countries who have failed to submit their latest national climate plan, Climate Home News reported, adding that about a third of countries are yet to submit more than a year after the deadline.

99%

The amount by which UK gas production in the North Sea is set to fall by 2050, when compared to 2025, as a result of a long-term decline in the basin.

97%

The amount by which North Sea gas production is set to decline from 2025 to 2050 if the government allows new drilling, according to new Carbon Brief analysis.

Latest climate research

• One-third of the world’s population lives in areas where heat and humidity would “severely limit activity for younger adults” | Environmental Research: Health
• The increase in extreme fire weather over 1980-2023 bears a “clear externally-forced signal” that is attributable to human-caused climate change | Science
• More than 85,000 social media posts from commuters in Boston, London and New York reveal “widespread thermal discomfort” in metro systems | Nature Cities

(For more, see Carbon Brief’s in-depth daily summaries of the top climate news stories on Monday, Tuesday, Wednesday, Thursday and Friday.)

Captured

Gas almost always sets the price of power in the UK and many other European countries, due to the “marginal pricing” system used in most electricity markets. A new Carbon Brief Q&A explored why this is the case and whether there are alternatives.

Spotlight

Japan’s ‘vulnerability’ to Iran energy crisis

Carbon Brief talks to experts about the implications of the Iran war for Japan’s energy and economy.

Japan, the world’s fifth largest economy and eighth largest greenhouse gas emitter, is among the countries reeling from the energy crisis fuelled by war in Iran.

Japan’s energy system is “structurally dependent” on imported fossil fuels, making the country “highly vulnerable” to geopolitical shocks, Yuri Okubo, a senior researcher at the Renewable Energy Institute in Tokyo, told Carbon Brief.

Japan currently imports 87% of its energy supply, with the vast majority of that coming from fossil fuels. According to the IEA, 36% of its total supply is met by oil alone.

Some 95% of Japan’s oil comes from the Middle East, with about 70% travelling via the Strait of Hormuz – a crucial shipping route currently under effective blockade, reported Reuters.

That means approximately two-thirds of Japan’s oil supply could currently be prevented from reaching its destination.

‘80 million barrels’

On Wednesday, as the International Energy Agency called for an emergency release of global oil reserves, Japanese prime minister Sanae Takaichi announced she would “release” 45 days of stockpiled oil, the largest volume in Japan’s history, according to the Asahi Shimbun.

This is only a portion of the 254 days of oil Japan has stockpiled, but if a supply shortage were to become severe, the prime minister may have to consider “restriction of energy usage”, like that seen during the oil shocks of the 1970s, Ichiro Kutani, director of the energy security unit at the Institute of Energy Economics, told Carbon Brief.

In 1973, the Organization of Arab Petroleum Exporting Countries (OAPEC) launched an oil embargo against countries suspected of supporting Israel during the 1973 Yom Kippur war, including Japan.

The subsequent shock for Japan’s economy was a major factor in the country’s shift from heavy industries to lighter industries such as electronics, academics have said.

Kutani told Carbon Brief:

“The failure to achieve the goal of reducing dependence on the Middle East for crude oil – pursued for more than 50 years since the 1970s oil crisis – is a bitter lesson.”

‘Nuclear’

On Monday, an opposition leader called on Takaichi to reopen Japan’s remaining fleet of nuclear power plants “as a carbon-free power source with less dependence on ​overseas sources”.

Prior to the Fukushima disaster in 2011, nuclear power provided roughly 30% of Japan’s electricity.

All 54 of Japan’s nuclear power plants were taken offline in 2011 after the Fukushima Daiichi nuclear plant meltdowns.

Over the past decade these have been slowly coming back online, but 18 out of 33 operable plants remain closed.

Takaichi has previously been vocal in her support of restarting Japan’s fleet of nuclear power plants, but developments in Iran “may add urgency to the debate”, Yuko Nakano of the Center for Strategic and International Studies told Carbon Brief.

Takeo Kikkawa, president of the International University of Japan, told S&P Global that the expansion of renewables has played a role in making up the shortfall from less nuclear power, adding:

“Now, with nuclear reduced to about 8%, renewables, especially solar, have increased to make up some of the difference. But overall, the combined self-sufficiency rate is still only about 15%.”

‘US-Japan summit’

Takaichi has so far resisted condemning or endorsing the attacks on Iran and refrained from making an assessment on the legality of US-Israeli strikes.

This could change next week, however, when she meets president Donald Trump for a US-Japan summit arranged before the war broke out.

In Washington DC, she may be expected to provide a more “full-throated endorsement” of the US war effort, “if not an outright request for Japan to dispatch its forces in support of US military activities in the Persian Gulf,” Tobias Harris, founder of Japan Foresight, a Japan-focused advisory firm in the US, said in a statement.

The Japanese government was already increasing oil imports from the US to diversify after the supply shocks from the Russia-Ukraine war – a trend that will likely be “further encouraged” by the Middle East war, said Dr Jennifer Sklarew, assistant professor of energy and sustainability at George Mason University. She told Carbon Brief:

“The overall effect of the war in the Middle East, thus, may be greater Japanese dependence on US oil and gas.”

Watch, read, listen

PLEDGE WATCH: The Cypress Climate Advisory group released a “NDC benchmarker” that monitors countries’ emissions against their nationally determined contributions (NDC) under the Paris Agreement.

FEMALE LEADERSHIP: A comment piece in Climate Home News explored why women’s leadership is “central” to unlocking the global phaseout of fossil fuels.

NOW OR NEVER: Martin Wolf, the chief economics commentator at the Financial Times, argued that one of the economic lessons from the Iran war is the “need to invest in renewables, in order to reduce vulnerability”.

Coming up

• 9-19 March: 31st Annual Session of the International Seabed Authority, Kingston, Jamaica
• 15 March: Republic of the Congo presidential election
• 15 March: Vietnam parliamentary election

Pick of the jobs

• Grantham Institute for Climate Change, assistant professor or associate professor | Salary: £70,718-£80,148 or £82,969. Location: London
• Centre for Research on Energy and Clean Air (CREA), China analyst | Salary: Unknown. Location: Remote/London
• Climate Action Network, campaign officer | Salary: £31,069-£33,140. Location: Flexible

DeBriefed is edited by Daisy Dunne. Please send any tips or feedback to debriefed@carbonbrief.org.

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13.02.26

The post DeBriefed 13 March 2026: War and oil | Why gas drives electricity prices | Japan’s ‘vulnerability’ to Iran crisis appeared first on Carbon Brief.

DeBriefed 13 March 2026: War and oil | Why gas drives electricity prices | Japan’s ‘vulnerability’ to Iran crisis

Climate change, war and mismanagement are putting Iran’s water supply under major strain, experts have warned.

The Middle Eastern country has faced years of intense drought, which scientists have found was made more intense due to human-caused climate change.

In recent years, Iranian citizens have protested against the government’s management of water supplies, pointing the blame at decades of poor planning and shortsighted policies.

As water supplies run low, authorities warned last year that several of Iran’s major cities – including the capital, Tehran – could soon face “water day zero”, when a city’s water service is turned off and existing supplies rationed.

Meanwhile, recent air strikes on desalination plants in Iran and Bahrain are driving wider questions about how the war might exacerbate water insecurity across the Middle East.

One expert tells Carbon Brief the conflict is “straining an already-fragile [water] system” within Iran.

In this article, Carbon Brief looks at how conflict is combining with climate change and unsustainable use to place pressure on Iran’s water supplies.

• How close are Iran’s major cities to a ‘water day zero’?
• What role is climate change playing?
• What other factors are involved?
• How could attacks on desalination plants impact water supplies in the Middle East?
• What policies could help Iran avoid a ‘water day zero’?

How close are Iran’s major cities to a ‘water day zero’?

Iran is one of the most water-stressed countries in the world and is currently in the grips of an unprecedented, multi-year drought.

The country’s hot and dry climate means that freshwater is scarce. However, many Iranian citizens also blame decades of government mismanagement for the present-day water shortages.

In January, the Guardian explained that over multiple decades, Iranian officials abandoned the country’s “qanat aquifer system”, which consists of tens of thousands of tunnels dug into hillsides across the country that lead to underground water storage. This system has been “supplying [Iran’s] cities and agriculture with freshwater for millennia”, the newspaper said.

To replace the aquifer system, the government built dozens of dams over the second half of the 20th century, which together hold around a quarter of the country’s total water resource, according to the Guardian. However, it added:

“But by putting major dams on rivers too small to sustain them, the authorities brought short-term relief at the cost of longer-term water loss: evaporation from reservoirs increased while upland areas were deprived of water, now trapped behind the dams.”

Yale Environment 360 noted in December that “in the past half century, around half of Iran’s qanats have been rendered waterless through poor maintenance or as pumped wells have lowered water tables within hillsides”.

Agriculture is responsible for 90% of Iran’s water use. Over 2003-19, Iran lost around 211 cubic kilometres of groundwater – around twice the country’s annual water consumption – largely due to unregulated water pumping for farming.

The images below show how Lake Urmia in the north-west of the country – once the largest lake in the Middle East – has almost completely dried up since 2001 as water that feeds that lake has been diverted.

Towards the end of 2025, Iran’s Meteorological Organisation warned that the main dams supplying drinking water to major cities, such as Tehran, Tabriz and Mashhad, were close to “water day zero”.

The term “water day zero” has been used by academics, media and governments to describe the moment when a city or region’s municipal water supply becomes so depleted that authorities have to turn off taps and implement water rationing. It has been used to describe water crises in Cape Town, South Africa and Chennai, India.

In a televised national address in November, Iranian president Masoud Pezeshkian reportedly said the government had “no other choice” but to relocate the capital due to “extreme pressure” on water, land and infrastructure systems.

(This came after the government announced in January it would relocate its capital to the southern coastal region of Makran, citing Tehran’s enduring overpopulation, power shortages and water scarcity.)

Tehran is home to 10 million people and consumes nearly a quarter of Iran’s water supplies.

The water shortages have fuelled nation-wide protests, which have been often-violently suppressed by the government.

Prof Kaveh Madani, former deputy vice-president of Iran and the director of the UN University Institute for Water, Environment and Health, tells Carbon Brief that recent rainfall means the threat of “water day zero” has subsided in Iran in recent months.

However, he stresses that a combination of climate change and “local human factors” mean “many, many places in Iran are in ‘water bankruptcy’ mode”.

“Water bankruptcy” is when water systems have been overused to the point they can no longer meet demand without causing irreversible damage to the environment, according to Madani’s own research.

Back to top

What role is climate change playing?

Iran is currently facing its sixth year of consecutive drought conditions.

An update posted in November by the National Iranian American Council quoted Mohsen Ardakani – managing director of Tehran Water and Wastewater Company – as saying:

“We are entering our sixth consecutive drought year. Since the start of the 2025-26 water year (about a month ago), not a single drop of rain has fallen anywhere in the country.”

The country’s most recent “water year”, which ran from September 2024 to September 2025, was one of the driest on record. Over the 12-month period, the country recorded 81% less rainfall than the historical average.

Meanwhile, temperatures in Iran can soar above 50C in the hot season, pushing the limits of human survivability and exacerbating water loss through evaporations from reservoirs of water.

Multiple attribution studies have shown that climate change is making the country’s hot and dry conditions more intense and likely.

In 2023, the World Wealth Attribution service (WWA) carried out an analysis on the drought conditions in Iran over 2020-23.

This study investigated agricultural drought, which focuses on the difference between rainfall amounts and levels of evapotranspiration from soils and plants.

The study explored how often a drought of a similar intensity would have occurred in a world without warming and how often it could occur in the climate of 2023. The researchers found that the drought would have been a one-in-80 year event without global warming, but a one-in-five year event in 2023’s climate.

They added that if the planet continues to heat, reaching a warming level of 2C above pre-industrial temperatures, Iran could expect a drought of 2023’s severity, on average, every other year.

The graphic below illustrates these results, where a pink dot indicates the number of years in every 81 with an event like the 2020-23 drought over Iran.

The box on the left shows how often such a drought would be expected in a pre-industrial climate, in which there is no human-driven warming. The box in the centre shows 2023’s climate, which has warmed 1.2C as a result of human-caused climate change. The box on the right shows a world in which the climate is 2C warmer than in the pre-industrial period.

Two years later, WWA carried out another study on drought in Iran, this time focusing on the five-year drought over 2021-25. The authors found an “even stronger impact” of climate change than their previous analysis.

A range of other attribution studies for Iran over the past five years have concluded that climate change made heatwaves and droughts over the region more intense and likely.

Meanwhile, the World Meteorological Organization’s (WMO’s) “state of the climate in the Arab region 2024” report warned about the impact of climate change on water security across the region.

In a statement, WMO secretary general Prof Celeste Saulo warned that “droughts are becoming more frequent and severe in one of the world’s most water-stressed regions”.

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What other factors are involved?

Climate change is not the only – or even the primary – driver of water scarcity in Iran.

Madani explains:

“We have both the human factors and the climatic factors…A lot of times, local human factors are much more important and significant than the global factors.”

For example, Madani says, the country has experienced large population growth, but its population is concentrated in “a very few large metropolitan” areas, meaning it can struggle to provide enough water to those places. He also points to inefficient agricultural practices and overreliance on technological solutions, including dams and desalination plants.

The vast majority of the country’s water stress comes from its agricultural sector, which accounts for more than 90% of Iran’s water use.

Dr Assem Mayar, an independent researcher focused on water resources and climate security, tells Carbon Brief that Iran’s arid climate means that it uses more water per unit area for cultivating crops than other countries. This issue is compounded by government policies promoting domestic agriculture, he says:

“[Iran’s] government tries to be self-reliant in [the] food sector, which consumes the most share of water in the country.”

Both of the country’s main water sources – surface water and groundwater – are overexploited, Mayar says.

A 2021 study on the drivers of groundwater depletion in Iran found that between 2002 and 2015, Iran’s aquifers were depleted by around 74 cubic kilometres – 1.6 times larger than the amount of water stored in Iran’s largest lake, Lake Urmia, at its highest recorded levels.

The study also found that some basins had experienced depletion rates of up to 2,600% in that timeframe.

Groundwater aquifers naturally “recharge” as water percolates down from the surface. However, a 2023 study also found that this rate of recharge has been declining since the early 2000s.

When groundwater or other resources are extracted from the ground in high quantities, the land above the aquifer can compact and the aquifers themselves can collapse, leading to “subsidence” as the land surface sinks. Iran is one of the countries with the largest subsidence rates in the world, according to a 2024 study.

In late 2025, BBC News reported that Iran had begun “cloud seeding” – injecting salt particles into clouds to promote condensation, in an effort to “combat the country’s worst drought in decades”.

The country has been employing the technique since 2008 and reports that rainfall increased by 15% in the targeted areas as a result.

However, this does little to address the root of the problem, experts tell Carbon Brief.

Prof Nima Shokri, director of the Institute of Geo-Hydroinformatics at Hamburg University of Technology, tells Carbon Brief:

“Iran’s water crisis stems primarily from decades of policy choices that prioritised ideological and geopolitical objectives over sustainable resource management. A costly foreign policy posture and prolonged international isolation have limited access to foreign investment, modern technology and diversified economic development.

“Domestically, this has translated into policies that encouraged groundwater-dependent agriculture, expanded irrigated land without enforceable extraction limits, maintained heavy energy and water subsidies and underinvested in wastewater reuse, leakage reduction and monitoring systems.”

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How could attacks on desalination plants impact water supplies in the Middle East?

A pair of attacks on desalination plants has led to significant media speculation around how the conflict might exacerbate freshwater supplies, both in Iran and across the Middle East.

On Saturday 7 March, Iran accused the US of attacking a desalination plant on Qeshm Island in the Strait of Hormuz.

Describing the attack on the critical water infrastructure as “blatant and desperate crime”, foreign minister Seyed Abbas Araghchi said water supply in 30 villages had been impacted.

The next day, Bahrain government said Iran had caused “material damage” to one of its desalination plants during a drone attack.

David Michel, senior fellow for water security at the Centre for Strategic and International Studies, told the Daily Mail that attacks on water plants in Gulf states by Iran could be designed to “impose costs” that push them to intervene or call for the end of the war.

There has been a boom in desalination across the Middle East in recent decades, as water-scarce countries have turned to the technology – which transforms seawater into freshwater – to boost freshwater supplies.

Collectively, the Middle East accounts for roughly 40% of global desalinated water production, producing 29m cubic metres of water every day, according to a 2026 review. This is shown in the chart below.

Iran has more than 163 desalination plants. However, it is less reliant on these plants than smaller countries in the region with fewer water reserves.

In a 2022 policy paper, the Institut Français des Relations Internationales noted Kuwait, Qatar and Oman sourced 90%, 90% and 86% of drinking water from desalination plants, respectively.

In contrast, an official from Iran’s state-run water company told the Tehran Times in 2022 that just 3% of the country’s drinking water came from desalination plants. (Iran’s water supply is sourced primarily from groundwater and rivers and reservoirs.)

Shrokri says the ongoing conflict is “hitting water security” in Iran through “direct and indirect” attacks on critical infrastructure – including desalination plants, power stations and water networks. He adds:

“The conflict is straining an already fragile system inside Iran. The country entered the war with severe drought, depleted groundwater and shrinking reservoirs, so any disruption to energy systems, industrial facilities or supply chains can quickly cascade into water shortages.”

Shokri also highlights that attacks on desalination plants in the Gulf could have serious consequences for major cities – including Dubai, Doha and Abu Dhabi – “rely heavily” on desalinated seawater for drinking water. He says:

“Without desalination plants, large parts of the region’s modern urban system will struggle to exist. The ripple effects would extend far beyond drinking water. Sanitation systems would begin to fail, public health risks would rise and economic activity could slow dramatically.”

Experts have pointed out that attacks on electricity infrastructure could also impact provision of drinking water, given desalination plants are energy-intensive and often co-located with power plants.

Dr Raha Hakimdavar, a hydrologist at Georgetown University, told Al Jazeera that attacks on desalination plants could also impact domestic food production in the long-term, if groundwater is diverted away from agriculture and towards households.

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What policies could help Iran avoid a ‘water day zero’?

Experts tell Carbon Brief that the conflict could make chronic water shortages in Iran more likely – even if hostilities are unlikely to directly force a “water day zero”.

Shokri says:

“The war could accelerate the timeline, but it didn’t create the risk of day zero. Iran’s water system was already under extreme pressure from long-term mismanagement and distorted policy priorities. Conflict simply reduces the margin for error.”

Mayar says the war is “unlikely to force day zero nationwide”, but could bring forward “localised day‑zero conditions in already stressed regions”. These effects could be felt most acutely in Iran’s islands and cities that are already “facing chronic shortages”, he continues.

Since agriculture is such a large contributor to the country’s water usage, potential solutions must focus on that sector, experts say.

Mayar says the government should “phase out subsidy policies that encourage overuse”.

In 2018, researchers at Stanford University released a “national adaptation plan for water scarcity in Iran”, as part of a programme looking at the country’s long-term sustainable development.

That report lays out two sets of adaptation actions: those that work to improve the efficiency of water use and those that end water-intensive activities. Among the specific actions recommended by the report are reusing treated wastewater, reducing irrigated farming and enhancing crop-growing productivity through technological solutions.

The adaptation report concludes:

“The underlying solution to address Iran’s water problem is obvious: consumption should be regulated and reduced, water productivity should be improved and wastewater should be treated and reused in the system.”

Meanwhile, Shokri argues that the “main obstacle” to water reform in Iran is not technical capacity, but “government-set national priorities”. He explains:

“Significant public resources are directed toward non-civil spending and external commitments, leaving limited room for sustained investment in water management and environment…Real progress will require shifting attention and resources toward water security, environmental protection and long-term economic resilience.”

Back to top

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The post Q&A: How climate change and war threaten Iran’s water supplies appeared first on Carbon Brief.

Q&A: How climate change and war threaten Iran’s water supplies

As countries scramble to secure oil, gas and fertilizer, China’s bets on clean energy and coal are cushioning its dependence on oil and gas imports.

By Nicholas Kusnetz, Georgina Gustin

When Gary Dirks arrived in China in 1995, the country’s government was looking to source more of its energy at home. Dirks was the incoming country head for BP, but efforts to find more oil and gas in the country had largely fizzled.

China’s Clean Energy Push Has Made It Less Vulnerable to Energy Shocks, Including the Iran War