Ethiopia's Tigray conflict: Nasa shows how a war zone faded from space

New images taken from space at night starkly show how the conflict in Ethiopia's northern Tigray region has left a population facing one of the world's worst humanitarian crises. Cities are shown fading to black over 20 months as electricity supplies are shut down.

The Nasa satellite photos have been shared with the BBC as Ethiopian troops and militias, along with soldiers from neighbouring ally Eritrea, appear to be gaining the upper hand against Tigrayan forces.

On Tuesday, Ethiopia said its army had taken control of Shire, one of Tigray's biggest cities, and the towns of Alamata and Korem, which lie to the south of the regional capital, Mekelle.

The UN, African Union and the US, among others, warn that the resurgence of heavy warfare could worsen the already catastrophic situation for civilians.

The Ethiopian government has not granted journalists access to Tigray since June 2021. With most communications cut off in the region, it's hard to report on the extent of the conflict and humanitarian crisis.

New data from the Tigray Bureau of Health, shared with the BBC, reveals how the blockade on the region - which has largely halted humanitarian aid as well as other services like electricity and banking - has affected young children.

The figures show that the number of those under the age of five who have died from malnutrition has risen by a staggering 1,533% over the two years from July 2020 - before the war broke out. That means for every child who died before the war, 16 died in 2021-22.

Dr Kokeb Hagos, who collates the Tigray Health Bureau data, told the BBC that 2,450 children had died in hospitals between July 2021 and July 2022 - a huge underrepresentation, he says, of the true figure as health workers cannot travel around the region because of a shortage of fuel while phone lines and the internet have also been cut.

Numbers have to be jotted down on pieces of paper and sent by any available transport to the bureau for collation, including the information that 70% of children found to be severely malnourished have not been treated because of a lack of food and medicine.

One of the children known to have died this year is Surafeal Mearig. The BBC first reported on his case in January 2022. At the time he was three months old and weighed just 2.3kg (5lb), 1kg less than he did at birth. His parents had run out of money to buy food after they lost their jobs. Doctors at Mekelle's Ayder Referral Hospital, where he was being treated, told us he died a month later.

In Nasa's Black Marble images (from November 2020 until August 2022) the trajectory of the conflict can almost be mapped - as they show light levels decreasing in the cities of Shire, Aksum and Mekelle. It is a monthly composite of the light emitted from the respective cities and an indication of their access to electricity.

Ethiopia's federal government controls the national power grid but has been accused of cutting off Tigray, where power was pretty consistent in the region's towns before the war, several sources have told the BBC.

According to an investigation published in September by the UN's International Commission of Human Rights Experts on Ethiopia, the government "suspended electricity, internet and telecommunications, and banking services in Tigray on 4 November 2020" - the day the conflict started.

The images show a sharp fall in light over the cities of Shire and Aksum from November 2020. The lights in the two cities get stronger between March and June 2021 when they are in government hands.

Mekelle remains well-lit until July 2021, just after the city was recaptured by Tigray forces. It had fallen within the first month of the conflict and remained bright during the seven months it was under government control.

"When Tigrayan forces retook control of large parts of Tigray, including Mekelle, in late June 2021, the federal government responded by again shutting down electricity, internet and telecommunications, and banking services for the region," the UN report says.

During the conflict the only major power source for Tigray's seven million people has been the Tekeze Hydroelectric Dam, which was bombed in December 2021.

The images show how the lights dimmed sharply in Mekelle later in December 2021 after the dam was bombed. This affected two of four turbines, according to Canada-based academic Getachew Assefa.

"Engineers are making two turbines active by utilising spare parts from the other two, but the condition is dire. Even the two turbines that are working are generating electricity inefficiently as they have several faults that could have been rectified if spare parts were accessible," the associate professor of sustainable design at Calgary University told the BBC.

Tigray is also home to the 84-turbine Ashegoda windfarm, dubbed Africa's biggest when it opened in 2013 near Mekelle, but it has been out of action during the conflict, says Prof Getachew.

Engineers there have managed to get 19 turbines working, but cannot get them to feed into a grid for Tigray alone.

There was a virtual blackout in Shire and Aksum in July and August 2021 and Mekelle gets darker and darker.

Some of the patchiness - especially in July and August this year - can be put down to seasonal levels of the dam, as the power plant is designed to be part of an integrated power supply and is unable to produce electricity all the time, Prof Getachew explains.

Ethiopia's government continues to deny blocking access to electricity, banks and communications in Tigray, though after seizing Shire this week, it promised access to humanitarian organisations in areas it now controls via the city's airport.

Sources on the front lines told the BBC the coalition of forces is now advancing eastwards from Shire and on to Aksum, Adwa and Adigrat.

This is almost a repeat of the start of the conflict nearly two years ago when the Ethiopian government seized Shire and went on to take the other towns before capturing Mekelle, which has been hit by frequent drone strikes especially since fighting restarted in August following a five-month humanitarian truce.

It is a terrifying time for the city's estimated 500,000 residents.

"The war has intensified. We are always wondering, when will the drone come? Will I find my children alive?" a nurse at the Ayder Referral Hospital told me.

One of the few aid workers left in the region said that her colleagues were now also going hungry.

"The remaining food has been depleted and the entire population is starving," she said. "Hundreds and thousands of desperate people knock on our doors seeking support. There are scores more starving in their homes, foregoing food for days on end."

They fear what will happen - especially possible reprisals from the Ethiopian and Eritrean troops.

For Prof Getachew, the war is bound to have a long-lasting impact on the region's infrastructure even if a blockade is lifted.

There are already reports of looting in Shire with allegations that items are being shipped back to Eritrea, as was reported to have happened widely in towns Eritrean troops took over early in the conflict.

"If true, they will continue with what is left of the electricity infrastructure."