HAMNET Report 27th June 2021

Severe weather has been battering large parts of the globe this week, mostly in the form of floods. India and Pakistan have both seen heavy rains and flooding in their northern regions, New Zealand was struck by a tornado last Saturday, France experienced heavy rain on Monday, Poland experienced heavy rain, as did Guatemala, flood warnings were issued for Belgium, Czech Republic and Romania, and Tropical Storm Claudette battered Southern and Eastern American states last weekend. At least 14 people died in Alabama, and many injuries were reported.

Meanwhile Southern Hungary and Southern Italy were warned to expect extreme high temperatures, and California experienced some of the hottest temperatures ever measured there.

Then, on Thursday the Czech Republic was struck by the worst tornado experienced since 2001, pummeling the Breclav and Hodonin districts. At least 5 fatalities were reported, more than 200 injured, many of them requiring hospitalization. Major parts of some villages were levelled to the ground, and about 120 000 people left without electrical power.

The long-tracked supercell storm destroyed numerous roofs from several hundred buildings between the Breclav and Hodonin districts, as well as uprooting trees and overturning cars. The worst-hit areas along the tornado path were reported looking like a war zone.

According to the meteorologist speaking on Czech TV, this tornado was the strongest in the Czech Republic’s history. The estimated intensity likely reached the F3-F4 scale. That means that winds could have reached between 267 and 322 km/h. Besides the tornado, very large hailstones up to the size of tennis balls struck several towns and villages including Hodonin.

Local rescue teams were receiving help from neighbouring Austria and Slovakia.

I received an email from a HAMNET member who wishes to remain anonymous who reports that, on the 2nd of June 2021 at approximately 22:00, a distress message was broadcast on a local security WhatsApp group, in Sedgefield, Southern Cape. A house was burning in Sedgefield and all initial attempts to contact the local fire brigade telephonically had failed.

Due to load-shedding and a UPS failure, the fire department’s telephone system was down. A local HAM attempted to contact the fire brigade via the fire-brigade’s VHF repeater. Unfortunately the repeater was also down due to the power-supply failure. Being situated at a somewhat elevated location, the HAM finally succeeded in making contact by reversing the repeater offset on his rig, thereby transmitting on the repeater’s output frequency.

It was established that the fire brigade was at that time busy extinguishing another fire in a home on the opposite side of town. Available vehicles were swiftly diverted to the house fire across town. The fire vehicles were still unable to communicate amongst each other. Therefore the HAM continued to relay messages between the different vehicles until all fire resources had arrived at the house-fire, the first fire having been successfully extinguished.

The improvised method of communication was not without challenges though. The individual vehicle’s operators talked over each other, as they naturally could not hear each other’s transmissions. With some patience, all critical information was however successfully relayed. Apparently only one room in the house was burnt out.

Thank you to our HAMNET friend for that report.

Phys.org is reporting that damage to Sri Lanka’s marine environment from a sinking chemical ship is worse than feared, officials said on Friday, as more dead turtles, dolphins and whales washed up on the island’s beaches.

As of Thursday, 130 marine animals have been found dead on the Indian Ocean’s beaches since the MV X-Press caught fire last month before partially sinking off the coast after two weeks ablaze.

Sri Lanka’s government believes the animals were killed by the hundreds of tonnes of chemicals and plastics leaking from the ship.

“At least six turtle carcasses washed up along the western coast on Thursday alone,” a wildlife official told AFP.

He said they had also received the first report of a shoal of reef fish dying at Hikkaduwa, a southern tourist resort area known for its rich coral reefs.

“So far we have collected the carcasses of 115 turtles, 15 dolphins and five whales,” the official said, asking not to be named.

They include a blue whale carcass found off the northern Jaffna peninsula, about 400 kilometres north of Colombo, last week. Officials are awaiting the results of forensic reports, he said.

The Singapore-registered ship was known to be carrying 81 containers of hazardous chemicals, including 25 tonnes of nitric acid, when it caught fire.

Around 1,200 tonnes of tiny plastic pellets and other debris that blanketed beaches have been scooped up and are being stored in 45 shipping containers.

Sri Lanka is seeking $40 million in damages from the ship’s operators X-Press Feeders. Local police have launched a criminal probe against the ship’s captain, chief engineer, chief officer as well as its local agent. Environmentalists are also suing the government and the owners for allegedly failing to prevent the disaster.

For the music lovers amongst you missing the pleasures of an orchestral concert as a result of the pandemic, Phys.org also reports that a team of researchers at the University of Utah Salt Lake City has found, via simulation, that it is possible to rearrange musicians playing wind instruments in an orchestra to reduce the spread of disease-laden aerosols. In their paper published in the journal Science Advances, the group describes simulations they ran that showed airflow patterns during orchestral performances and what they found.

To learn more about the flow of air and the aerosols in it during orchestral performances, the researchers gathered data from prior experiments showing how air moves after being expelled from different instruments. This data was put into an air movement simulation, along with other parameters, such as ventilation for the given venue.

The team then began tinkering with the seating arrangements and discovered that by making certain changes they could reduce the viral load in the air where the musicians were playing. They found, for example, that putting percussionists closer to the centre of the group and those playing wind instruments around the fringes—and as close as possible to air vents—they could dramatically reduce the spread of aerosols. In studying the data, they found that the new seating arrangement reduced concentrations of virtual viral loads by a factor of 100.

In essence then, if you must blow your own trumpet, please go and blow it somewhere nearer the window!

This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.