The heatwave gripping the northern hemisphere has encouraged a spate of creative solutions to help cool the blood, from a frozen nightclub in Berlin to pickled plums in Tokyo.

In South Korea, where all-time record temperatures led to the deaths of 28 people this week– the hottest place hit 40.3C (104.5F) – people have been flocking to air-conditioned shopping centres, many of which reported a 20% rise in visitor numbers. Food delivery companies have also benefited as many city residentsreluctant to leave their air-conditioned flats order meals online.

Vests full of ice cubes or cooling gel have become increasingly popular as have portable battery-driven and solar fans.

Women in traditional dress shield their faces from the sun as they cross a street in Pyongyang. Photograph: Ed Jones/AFP/Getty Images

Across the border in North Korea, which lacks the electricity to run air conditioning in many buildings, people have reportedly taken to jumping in streams, rivers and reservoirs instead. The consumption of dog meat, traditionally eaten on hot days because it is said to boost stamina, is also said to have soared.

People in Japan have been coping with the heat by snacking on pickled fruit. Highly salted plums known as umeboshi are a summer favourite because they are thought to help replenish salt lost in sweat.

At an umeboshi factory in Japan’s Wakayama prefecture, a leading plum-producing region, orders have surged by between 50% and 100%, the national broadcaster NHK reported.

In Tokyo, where the mercury topped 37C on Thursday, mist fans have been set up in public places to spray passersby who need to cool off. It is the same technology that organisers of the Tokyo 2020 Olympics plan to deploy.

Many Japanese residents have also been spotted wearing pads on their foreheads.

In Germany, where temperatures have been in the 30s for days, people have sought relief everywhere from museums to deep freezes. Museums from Munich to Nuremberg report an increase in the number of visitors, many of them seeking refuge in the air-conditioned rooms.

Drinkers seek relief from the heat in an ice bar in Berlin. Photograph: Miriam Karout/AP

A supermarket in the western state of Hesse is offering its customers two minutes in its cold-storage room at a cost of €3 (£2.70) a time.

Lars Koch, the manager of the supermarket in Friedberg, told Spiegel: “It’s been 37 degrees here for several days now … This isn’t a marketing gag as some have suggested, and won’t make me rich, but a serious offer, and quite a few people have been crazy enough to take it up so far.”

In Berlin, where police have been called to public swimming pools to quell riotous bathers after they were banned from entering because of overcrowding, one nightclub has been doing a roaring trade.

The Angiyok, built by eight sculptors from 60 tonnes of ice, offers temperatures of -10C, with thick jackets available for those for whom the cold becomes too much.