A frontpage story in the Financial Times reports that UK chancellor Philip Hammond has warned prime minister Theresa May that reducing greenhouse gas emissions to net-zero by 2050 could cost the UK over £1tn. The FT reports that a letter from the chancellor, which it has seen, says the cost would mean less money available for schools, police, hospitals and other areas of public spending. “He also warned that the target would render some industries ‘economically uncompetitive’ without huge government subsidies,” adds the FT. The 2050 net-zero target was recently recommended by the Committee on Climate Change (CCC), the UK’s independent climate advisory body. The CCC estimated that reaching net zero will cost £50bn a year, but the Department for Business, Energy and Industrial strategy puts the figure at £70bn, according to the chancellor’s letter. “On the basis of these estimates, the total cost of transitioning to a zero-carbon economy is likely to be well in excess of a trillion pounds,” he says, according to the FT. [In its advice on going net-zero, reported last month by Carbon Brief, the CCC says the costs will be at least partially offset by “large benefits” – not mentioned in the FT’s reporting of the chancellor’s letter. The CCC also says the costs will be similar to those already accepted by parliament when it legislated for the existing 80% by 2050 goal.]

Meanwhile, in a letter to the FT, Prof Sam Fankhauser – director of the Grantham Research Institute on Climate Change at the London School of Economics – warns that reports “the UK government is allegedly preparing to use previous overperformance in reducing carbon emissions when calculating its carbon budget for up to 2027 indicates a worrying willingness to game the system on meeting crucial climate change targets”.

New research says that thousands of heat-related deaths in major US cities could be avoided if rising global temperatures are curbed, the Guardian reports. The study projects future heat deaths in 15 US cities under different levels of future warming – the 1.5C and 2C goals of the Paris Agreement and 3C. The findings show that “in almost every city they considered, the more global temperatures rose, the more people will die,” says the New York Times. The greatest risks are in northern cities such as Philadelphia, New York and Boston, the paper notes. “This shows the substantial public health benefits of reaching the Paris goal,” the lead author tells InsideClimate News. The Hill and MailOnline also cover the research, as does Carbon Brief, which has an interview with the lead author, recorded at the fall meeting of the American Geophysical Union last year.

In her first article as energy correspondent for the Guardian, Jillian Ambrose reports that the Labour party has accused the government of “actively dismantling” the UK’s solar power industry after new installations by households collapsed by 94% last month. “Rebecca Long-Bailey, the shadow business secretary, used prime minister’s questions to challenge the government’s record on climate action after scrapping subsidies for domestic solar panels from April,” says Ambrose. She reports that Labour said ending the subsidies caused new solar power capacity additions to fall from 79 megawatts (MW) in March to only 5MW last month. Long-Bailey said solar power had the potential to cut household bills and carbon emissions while creating thousands of jobs, “but the government, for some reason, appears to be determined to kill it off, while continuing to cheerlead for fracking”, the Guardian adds. Long-Bailey also questioned the government’s authority on climate change, reports another piece in the Guardian: “Three current ministers have denied the scientific consensus on climate change. And several of those standing in the Tory leadership contest have close links with organisations and individuals promoting climate change denial.” And iNews reports that Long-Bailey also said the Labour Party would not reopen coal mines if it was in government – contradicting comments made by Labour leader Jeremy Corbyn in 2015. Long-Bailey told MPs that “the Labour Party does not condone the reopening of any coal mine to be used for energy purposes”.

Public concern about the environment has risen “to record levels in the UK since the visit of Greta Thunberg to parliament and the Extinction Rebellion protests in April”, reports the Guardian. The environment is now cited by people as the third most pressing issue facing the nation in tracking data from the polling company YouGov, which began back in 2010 – as first reported last month in a Carbon Brief guest post. “Environment was ranked after Brexit and health, but is ahead of the economy, crime and immigration,” the Guardian notes. The Canaryalso has a story on the surge in concern in the UK about climate change.

Joe Biden’s Democratic presidential campaign has amended his climate policy plan hours after it was released yesterday, reports the Guardian, “because a handful of passages did not credit some of the sources in the proposal, prompting allegations of plagiarism”. “The changes come after the conservative Daily Caller and others reported that several passages from Biden’s plan appeared to borrow from policy papers and statements written by outside groups without citation,” explains the Guardian. These borrowed statements came from “various advocacy organisations, policy shops, and in one instance a Vox article”, says Vox. Biden’s plan promises to crack down on financing of coal power around the world by China, reports Climate Home News. It reports that the Biden plan says China, through its belt and road initiative, is “annually financing billions of dollars of dirty fossil fuel energy projects across Asia and beyond”. The plan, which would see the US aim to be carbon neutral by 2050, “shows how far the Democratic field is moving on climate change”, says the New York Times.

Elsewhere in the race for the Democratic nomination, Reuters reports that Jay Inslee released a “sweeping plan on Wednesday to reclaim US leadership in the fight against climate change that includes proposals to resettle hundreds of thousands of climate refugees, and raise barriers to fossil fuel imports”. And Vox looks at how “climate change is becoming a defining issue of [the] 2020 [election]”.

Budget airline Ryanair has for the first time published monthly figures for its CO2 emissions, reports the Financial Times. Ryanair’s figures show it emitted 1.2m tonnes of CO2 in May, which is “roughly the same amount that New York City produces in a week”, notes the FT. “The figures, which represent the first time a European airline has published monthly CO2 data, come as Ryanair faces mounting pressure from consumers and environmental groups over its emissions,” the article adds.

There is continued coverage and reaction to the comments made by US president Donald Trump to Prince Charles that “climate change goes both ways”. Writing in the Washington Post, national correspondent Philip Bump says “Trump doesn’t seem to have ever articulated an understanding of [climate change] that scientists are presenting, choosing instead to talk in gauzy terms about clean air”. “Asked whether he and Charles spoke about climate change, Trump said that he wants the US to have clean air and water,” says Bump, adding that: “It occurred to me that I’ve never really heard Trump talk about CO2 as a contributor to climate change.” Bump’s analysis of Trump’s speeches shows the only mention he appears to have made of CO2 contributing to warming was in announcing the US withdrawal from the Paris climate accord – “while reading from a pre-written speech”. Also writing in the Washington Post, opinion writer Jennifer Rubin sympathises with Prince Charles as he tried to “educate the Climate Change Denier In Chief”. “Poor Charles will never get that 90 minutes of his life back,” she says: “However, it does show that Trump is peculiar in showing off his ignorance, failing to recognise how bizarre he sounds to all but his followers.” Rubin concludes: “Trump remains utterly unconvinced that climate change exists, let alone is a serious threat, relishing his own ignorance and refusing to admit he might not know what the heck he is talking about. Sorry, Prince Charles, we share your utter exasperation.”

BBC News, the Daily Telegraph and the Press Association all have continued news coverage of Trump’s comments. And the Guardian’s environment correspondent Fiona Harvey finds eight reasons why Trump’s claim that the US has “among the cleanest climates there are” is wide of the mark.

A new paper looks back at how the “climate spiral” visualisation of rising global temperatures, created by Prof Ed Hawkins at the University of Reading, spread worldwide using both traditional and social media. “The animated global temperature spiral was one of the first climate graphics to ‘go viral’, being viewed by millions of people online and by more than a billion people when it was used in the opening ceremony of the 2016 Rio Olympics,” the paper says. The authors acknowledge the contribution of Carbon Brief’s Dr Simon Evans “for producing a small enough version of the animated graphic to be uploaded onto Twitter initially”.

A new study of the Douro Valley of Portugal suggests a shift to a warmer and drier climate could push conditions outside the “range for quality wine production in the long‐term”. Researchers used downscaled climate model simulations for the Douro Valley for the middle and end of this century. The results suggest that a moderate increase in very hot days and drought at certain points in the growing season could “have a positive association with vintage ratings”. However, in a high emissions scenario, conditions move outside the ideal range in the mid and long-term. The authors conclude: “These results indicate potential impacts that suggest a range of strategies to maintain wine production and quality in the region.”

Providing drinking water stations for koala bears during heatwaves and droughts can help relieve the risk of death due to dehydration, a new study suggests. Koala bears are commonly thought to get all their hydration from eating leaves; this puts them at risk from the increasing frequency and severity of extreme weather events, the researchers say. However, experiments using artificial water stations – conducted in New South Wales, Australia – find that koalas freely used the water and their time spent drinking varied with season and depended on days since last rain and temperature. “Our results suggest that future changes in rainfall regimes and temperature in Australia have the potential to critically affect koala populations,” the researchers conclude.