Ukraine: Russia and Ukraine engaged in fierce drone attacks this week after Ukraine claimed it had killed one of Russia’s most senior naval commanders in a strike in Crimea that left 34 officers dead.

Ukraine’s special forces on Monday said its attack had destroyed the headquarters of Russia’s Black Sea fleet during a meeting of officers that included the head of the fleet, Admiral Viktor Sokolov, who had held the post since September last year. On Tuesday, Russia’s defence ministry released footage it said showed Sokolov at a meeting of defence leaders that day. The Kremlin said the defence ministry had not provided any information about Sokolov’s alleged death.

Russia this week launched a barrage of missile, drone and artillery strikes, including attacks that destroyed grain infrastructure in the ports of Odesa and Izmail. Six people died in the attacks. Russia claimed it had shot down Ukrainian drones over Crimea and two regions in Russia.

Separately, a United Nations investigation reported this week that it found torture and rape by Russian forces in Ukraine had been “widespread and systematic”.

Erik Mose, who headed the investigation, told a hearing at the UN Human Rights Council that “frequently, family members were kept in an adjacent room, thereby forced to hear the violations taking place”.

Russia did not send a representative to the hearing.

United States: Joe Biden hosted a two-day summit with leaders from the Pacific Islands in Washington this week as part of a bid to counter China’s growing reach in the region.

The gathering, which followed a similar summit hosted by the US president last year, included representatives from 18 Pacific nations.

The prime minister of Solomon Islands, Manasseh Sogavare, who has been forging close ties with Beijing, did not attend, even though he had just been in New York for the UN General Assembly. Officials in Solomon Islands claimed Sogavare, who visited China in July, had to return home for parliamentary business. A White House official said the US was “disappointed” at Sogavare’s absence.

In his address to the UN, Sogavare said China’s development cooperation was “less restrictive, more responsive and aligned to our national needs”. He also criticised the region’s “toxic mix of geopolitical power posturing”.

The other notable absence from the summit was Vanuatu’s new prime minister, Sato Kilman, who stayed in Port Vila to try to retain his shaky hold on power.

Pacific leaders have criticised the geopolitical rivalry in the region, saying their main priority is climate change.

On Monday, Biden told the summit he accepted concerns in the Pacific about the existential threat of rising sea levels. He promised US$200 million to support climate change mitigation, economic development and public health projects, and to combat illegal fishing.

“We hear your calls for reassurance that you never, never, never will lose your statehood or membership of the UN as a result of a climate crisis,” he said.

The White House, which has been opening embassies across the region, said it would establish diplomatic recognition of Niue, which has just 2000 residents, and of Cook Islands, which has about 8000 residents and is a self-governing nation in free association with New Zealand.

Azerbaijan: Armenia accused Azerbaijan of conducting ethnic cleansing in the disputed Nagorno–Karabakh region this week after Azerbaijani forces reclaimed control of the enclave, prompting a mass exodus of ethnic Armenians.

Azerbaijan has been blockading the tiny territory for months, preventing food and medicine from entering and raising concerns about a potential genocide. The enclave, which is inside Azerbaijan and is internationally recognised as belonging to Azerbaijan, has an ethnic Armenian majority, which had formed a breakaway government.

Last Sunday, Azerbaijan launched a successful 24-hour offensive that forced the breakaway government to agree to a ceasefire and to dismantle its armed forces. The enclave is now set to be reintegrated into Azerbaijan. Armenia said the operation left 200 people dead and 400 wounded.

By Tuesday, more than 28,000 ethnic Armenians from Nagorno–Karabakh – or almost a quarter of the population – had fled to Armenia, due to fear of reprisals. At least 68 people waiting for fuel to flee the enclave were killed and 300 were injured when a fuel storage depot exploded on Tuesday, though the cause was unknown.

Representatives of the breakaway state this week called for the United Nations to oversee security in the enclave.

David Babayan, an official, told Reuters “99.9 per cent prefer to leave our historic lands”.

The area covered by the sea ice that surrounds Antarctica has hit a record low after failing to recover during winter.

The US National Snow and Ice Data Center (NSIDC) revealed on Monday that the area covered by sea ice after the recent winter peaked on September 10 at 16.96 million square kilometres – about a million square kilometres less than the previous record low in 1986. Of the eight lowest amounts on record, four have occurred since 2018.

The sea ice is crucial to protect the continent’s glaciers and ice and to help prevent further rises in ocean temperatures.

Some of the reduction in sea ice this winter was caused by storms that pushed sea ice against the landmass, but the bulk of the loss could not be explained by seasonal weather. According to the NSIDC, the sea ice around Antarctica took a “sharp downturn” in 2016 that has steadily continued and is believed to be due to warmer ocean temperatures.

“There is some concern that this may be the beginning of a long-term trend of decline for Antarctic sea ice, since oceans are warming globally, and warm water mixing in the Southern Ocean polar layer could continue,” the centre said in a statement.

Antarctica and the Arctic are both believed to be warming at faster rates than the rest of the world, causing environmental havoc. Late last year, melting sea ice in Antarctica caused the mass wipeout of emperor penguin chicks, which drowned or froze because they had not yet developed the feathers required to swim. About 10,000 young penguins died.

Gail Whiteman, of the University of Exeter in Britain, told The Washington Post the latest sea ice data from Antarctica was “not great news”.

“Polar ice is one of the world’s biggest insurance policies against runaway climate change, and we can see in both the North and the South sea ice, we’ve got problems and alarm bells are ringing,” she said.