MOSCOW – MOSCOW (AP) — A miasma of smoke from wildfires cloaked the sweltering Russian capital on Friday, turning the city's spires into ominous blurs and grounding flights while glum pedestrians trudged the streets with faces hidden by surgical masks and water-soaked bandanas.
The smoke crept into many buildings, hovering about the ceiling in entryways. The State Historical Museum, on Red Square was forced to close because it couldn't stop its smoke detectors from going off.
Airborne pollutants such as carbon monoxide were four times higher than average readings — the worst seen to date in Moscow, city health officials reported. The concentration appeared likely to intensify; the state news agency ITAR-Tass reported smoke was thickening in the city's southeast late Friday.
The fires, which are raging across much of western Russia, come after weeks of extraordinary heat — daily highs of up to 100 (38 C) compared with the summer average of 75 — and practically no rain.
Natural Resources Minister Yuri Trenev said Friday that there's no water shortage yet because officials had kept reservoir levels high. But he noted that river levels are down by more than 20 percent, due to increased demands for water to battle the fires and practically no water flowing in.
The fires drew comment from officials and activists at international climate-change talks in Bonn, Germany.
Chief U.S. delegate said Russia's situation and the recent floods that have devastated Pakistan are "consistent with the kind of changes we would expect to see from climate change and they will only get worse unless we act quickly."
But the environmental group Greenpeace said the negotiators weren't getting the message.
"Russia is burning and Pakistan is drowning -- yet they seem happy to continue as if they have all the time in the world," the group's climate policy director Wendel Trio said in a statement from Bonn.
Dozens of flights were grounded and others were diverted away from the capital's airports as visibility deteriorated to as little as 200 yards (meters) during the day. By Friday evening, the three airports reportedly were resuming normal service.
Visibility in the capital was down to a few dozen yards due to the smoke, which is forecast to hang around for days due to the lack of wind.
"It's just impossible to work," said Moscow resident Mikhail Borodin, in his late 20s, as he removed a face mask to puff on a cigarette. "I don't know what the government is doing, they should just cancel office hours."
Russian health officials have urged those who have to go outdoors to don face masks and told people staying inside to hang wet towels to attract dust and cool the airflow. The Health Ministry said hundreds have needed medical attention due to the smog.
Ken Donaldson, professor of respiratory toxicology at the University of Edinburgh, said people with asthma, bronchitis, lung disease or heart problems were the most vulnerable to the smog.
"For people with underlying health problems, the particles in the smog could be the straw that breaks the camel's back," he said, causing them to have a serious lung problem or a heart attack.
He said concentrations of carbon monoxide, even at four times higher than normal, was not alarming unless people became trapped in an enclosed space. The more dangerous gases are ozone or sulfur dioxide, he said, but those are not usually produced by burning.
More than 500 separate blazes were burning nationwide Friday, mainly across western Russia, amid the country's most intense heat wave in 130 years.
"All high-temperature records have been beaten, never has this country seen anything like this, and we simply have no experience of working in such conditions," Moscow emergency official Yuri Besedin said Friday, adding that 31 forest fires and 15 peat-bog fires were burning in the Moscow region alone.
At least 52 people have died and 2,000 homes have been destroyed in the blazes. Russian officials have admitted that the 10,000 firefighters battling the blazes aren't enough — an assessment echoed by many villagers, who said the fires swept through their hamlets in minutes.
To minimize further damage, Russian workers evacuated explosives from military facilities and were sending planes, helicopters and even robots in to help control blazes around the country's top nuclear research facility in Sarov, 300 miles (480 kilometers) east of Moscow.
A wildfire last week caused huge damage at a Russian naval air base outside Moscow.
Moscow faces temperatures approaching 38 degrees Celsius (100 Fahrenheit) for the next week, according to the forecast, in contrast to its average summer temperature of around 23 C (75 F).
Associated Press writers David Nowak and Mansur Mirovalev in Moscow, Arthur Max in Bonn and Medical Writer Maria Cheng in London contributed to this report.