A magnitude 7.3 earthquake struck Chile close to the Bolivian border on Friday morning the 19^th July at 03h50 Central African time, exposing a population of about 140000 to Magnitude 7 shaking. By Friday evening, no reports of casualties had trickled through yet

You will have noted that two South African provinces were declared disaster areas this week, and for opposite reasons. KwaZulu Natal had parts of the province given disaster status as a result of extreme heat and uncontrollable fires, which claimed some lives amongst firefighters and the public, and the weather hasn’t abated there yet, so disaster management teams and firefighters remain on alert.

And the Western Cape was declared a disaster area as a result of very high rainfall, and damaging winds and storm surges, after a succession of cold fronts battered the Cape. As I mentioned last week, the informal settlements scattered along river banks and in low-lying areas were generally washed away, and this week, starter kits of materials with which to rebuild houses were issued out to many destitute residents.

And rain-wise, this week was no better. I live in a central Peninsular area, where rainfall is usually milder than the classical wet areas, like Newlands and Rondebosch, but even I broke my previous records for the most rain in one calendar month, since I started keeping records in 2001. Since Wednesday the 3^rd of July, I have recorded 271 mm of rain, soundly beating my previous record of 247 in August 2013. And we still have another 10 days of July to get through. In the last six days, I have recorded 144mm, but I’m sure places like Newlands, the Tygerberg and the catchment areas of the main dams serving the Western Cape will have experienced 2-3 times as much. I believed those same dam’s increased their levels by 20 percentage points this week alone.

I give thanks that our rain doesn’t all arrive in one day, like KZN experiences, and bridge wash-aways and loss of life is not as marked. Meanwhile, the inland high ground is threatened with snowfalls, particularly over the Ceres, Cedarberg and Koue Bokkeveld area, as well as the Sani Pass and Giant’s Castle portion of the Drakensberg, and the south-eastern tip of Lesotho. Winter ain’t over yet!

BBC.com pertinently asks the question: Do tornadoes or hailstones do more damage?

The world is devastated by 1000’s of tornadoes each year. Yet, in 2023, heat claimed more than double the fatalities caused by tornadoes, surprisingly, and hail can account for 60-80% of insured losses from thunderstorms – more than tornadoes do.

To those who have only experienced mild hail, the icy sprinkles may seem harmless by comparison. But hail can unleash a torrent of chaos. In June, a plane travelling from Spain to Austria had its nose cone ripped away and its cockpit windows smashed after flying into a hail storm. In 2018, softball-sized ice pummelled a Colorado zoo, killing two birds and injuring 14 people. And, although rare, hail can be fatal to humans too, with eight deaths recorded in the last 70 years.

Tornadoes get a lot of publicity, but hailstorms can span kilometres and last hours, and do far more general damage. Their reach and frequency means hail storms are a particular challenge for the insurance industry. According to Ian Giammanco, a meteorologist and managing director of standards and analytics at the Insurance Institute for Business and Home Safety (IBHS), only about 10% of all hail-producing thunderstorms cause damage – but those that do, wreak havoc, with hail accounting for “more than $10bn in the Americas in insured losses every year since 2008”.

At just 2.5cm hail can start to damage vegetation, Giammanco says. By 3.8cm, it can dent cars and older, shingle roofs. By 5cm it cracks car windshields and damages most building materials typically used in US construction. Bigger than 5cm, hail has the potential to crack plywood decking and at 10cm it can come through your roof.

Climate change is strengthening storm updrafts, according to an upcoming paper by Prof Vittorio Gensini and colleagues. Updrafts work like a hairdryer pointing upwards, Gensini explains; the stronger the thrust of air, the larger the ice-ball you could balance at its top. Therefore as the updrafts become stronger, bigger hailstones can be created. However, the warming climate is also causing more, smaller hailstones to melt before they hit the ground, he counters. 

Unfortunately, the two threats – hail and tornadoes – commonly are found close together. The strongest, rotating and tornado-forming thunderstorms – known as supercells – are produced by the same atmospheric conditions that are also likely to create hail. 

So in essence, you get whacked on the roundabouts as well as on the swings!

Very exciting this week was the monitoring of the sunspot number, which on Thursday, Friday and Saturday reached a staggering figure of 275 (gathered together in groups of course), only 10 sunspots less than the record of 285 measured during the peak of solar cycle 19, in March 1958, the best solar cycle ham radio has ever experienced. I personally listened to one of my Elmers working Hawaii (KH6) on 2watts USB on 20 metres from ZS5-land at that time! Let’s hope it happens this cycle too. Folks, turn on your radios and listen around!

In a short paragraph written for Hackaday by Jenny List, she wonders whether hackers are the future of amateur radio.

She says “If amateur radio has a problem, it’s that shaking off an image of being the exclusive preserve of old men with shiny radios talking about old times, remains a challenge. Especially, considering that so many amateurs are old men who like to talk a lot about old times. It’s difficult to attract new radio amateurs in the age of the Internet, so some in the hobby are trying new avenues. Dan, KB6NU went to the recent HOPE conference to evangelise amateur radio, and came away having had some success. We agree with him, hackers can be the future of amateur radio.

“In the slides from his talk, he goes through all the crossovers between the two communities from Arduinos to GNU Radio. We don’t need persuading; in fact we’d have added UHF and microwave RF circuitry and pushing the limits of the atmosphere with digital modes such as WSPR to the list as our personal favourites. It seems he found willing converts, and it’s certainly a theme we’ve featured before here at Hackaday. After all, unless it retains its interest, amateur radio could just die away.”

I’m not sure that amateur radio will just die away, but I do agree that the hacker mentality will certainly add to the enterprising spirit needed to keep amateur radio interesting to the new ham. What do you think?

This is Dave Reece ZS1DFR reporting from a soggy Cape Town for HAMNET in South Africa.

Over last weekend, Tropical Cyclone BERYL, which had weakened as it drifted west-north-west towards Mexico’s Yucatan Peninsula, changed its mind, turned sharp right and swept across about 50 of Texas’ lower counties. A state of disaster in that half of Texas was declared last Friday, as the storm brought the potential for damaging winds, heavy rainfall and a storm surge that could push waters up by a couple of metres along the Texas coastline.

The Global Disaster Alert and Coordination Centre (GDACS) summarizes the final statistics arising from the hurricane as including 28 fatalities in various countries and many thousands of affected or displaced persons. What was unusual about Beryl was how early in the hurricane season such a severe storm arose, and how quickly it transformed from a storm warning to a stage 5 hurricane. I hope this is not a forewarning of things to come this season.

In other parts of the US, extreme temperatures were being measured. In Arizona’s Death Valley, the record for the highest temperature ever recorded there was broken this week, at a touch over 53 degrees Celsius! And apparently some people were foolish enough to congregate there just to be able to experience the heat, in the knowledge that their vehicles might overheat, and blow a head gasket, trapping them in the life-threatening temperatures. There doesn’t appear to be any medication for madness!

Meanwhile, the South African weather services were warning of a series of cold fronts, striking the south western Cape coastline in quick succession, and bringing heavy rains, very strong winds, and flooding to low-lying areas.

And, as you have most probably seen, the Municipality of Cape Town, plus Stellenbosch and Overberg municipalities were devastated by huge amounts of rainfall, of the order of 200-300 mm of rain between last Sunday the 7^th and today. Masses of homes were flooded, families had to be evacuated away to dry community halls and rescue centres, roads and embankments were washed away, trees were uprooted, and infrastructure like clean water supply and electricity devastated.

It is not over yet. Another 40mm of rain is forecast between today and the end of this coming week, before the cloud and precipitation leaves us. I don’t think the Western Cape experiences those flash-flood type storms that strike the border areas with Mozambique and in KZN for example. We don’t experience such loss of life, but the effect of the weather and the very cold winter months make surviving in a wet home, with nothing dry to keep warm under, or even wear, very unpleasant, and contribute to a different type of disaster that takes many weeks to recover from.

Unfortunately the citizens in the areas who suffer the most are the informal dwellers, who have to be content with self-built non-waterproof shacks on low-lying ground, and it doesn’t take more than a rise of 50cm in the water table to flood all the dwellings. Disaster Management Agencies in the province run round in circles, helping in area after area, just in time for the next cold front to strike, and the next informal settlement to be flooded.

We hope to see the end to this rash of cold fronts during the course of the coming week. Of course, maximum temperatures don’t get much above 14 degrees, and humidity remains in the 80 to 90 percent range, so nothing dries, even though it is not raining. Very dismal indeed.

HAMNET Western Cape has been on standby, and nets on HF have continued, to make sure that outlying hams are safe, and also to make sure message traffic can be passed if areas get cut off. So far, we have not been needed. Luckily, in this weather, people are not foolish enough to try hiking up Table Mountain, so searches and rescues have been down to the minimum. The Table Mountain Cable Car system is not running anyway, as it undergoes its annual maintenance in July, so people realize that if they walk up Table Mountain, they’re jolly well going to have to walk down again, and a slippery mountain is a treacherous mountain!

The cold Antarctic air that always comes in after a major cold front in the Western Cape, is responsible for snow alerts for the Western, Northern and Eastern Cape, and Free State, as well as very cold conditions in the northern Provinces, as well as for the strong winds and veld fire warnings in KZN, which has their disaster management agencies also on high alert.

Meanwhile, Dr Imtiaaz Sooliman, of “Gift of the Givers” has repeated his call for a single organization countrywide to manage disasters. He says that, with disaster management on many tiers in each province, and often on different tiers in each province, it becomes very difficult to know how best to respond, and who to approach for the right kind of governmental response, or disaster funding in each province. Things are too fragmented, he says.

Often he has wondered “who is in charge?”, and notes that with many agencies with varying degrees of capability, it is easy for responsibility to be passed on to someone else, thereby shifting “blame” when reactions to disasters are being orchestrated.

The ARRL has distributed a paragraph saying that, at Ham Radio 2024, the International amateur radio exhibition, last week in Friedrichshafen, Germany, the Software Defined Radio Academy (SDRA) celebrated its 10-year anniversary. Founded in 2014, the SDRA has become a new platform for the exchange of knowledge surrounding software defined radio. In the early years, the academy’s lectures were recorded with primitive camera technology, but today a video team takes the recordings to a completely different level. The SDRA’s YouTube channel now has 150 uploads, 4850 subscribers, and many more views of the videos.

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

Last Saturday the 29^th of June, messages started arriving of the first big Tropical Cyclone of the season in the Caribbean rearing its head. Named BERYL, it was travelling virtually due West and threatening Barbados, Trinidad and Tobago, Saint Lucia, Saint Vincent and the Grenadines, Grenada, Dominican Republic, Haiti, Jamaica, the Cayman Islands and eventually Mexico with winds of up to 270km/h. The alert level was classified RED.

By Wednesday, the Hurricane Watch Net had been activated at the National Hurricane Centre, to watch BERYL, now classified as a Category 4 storm, saying that it was expected to make landfall in the Yucatan peninsula of Mexico by Friday. WX4NHC was monitoring 14.325MHz and 7.268MHz as its primary frequencies.

2.3 million persons were in its expected path. Jamaica declared a 7 day state of disaster from Wednesday to cover the expected duration of severe weather over the island and imposed an island-wide curfew between 06h00 and 18h00 local time on Wednesday to reduce the likelihood of unnecessary injuries during the severity of the storm.

By Friday, GDACS had tallied up seven fatalities, five persons missing and 500 evacuated to shelters in Jamaica.

Greg Mossop G0DUB of IARU Region One issued a long list of emergency HF frequencies being used by amateurs in most of the Caribbean Islands, too long a list to quote here. He asks for IARU Region One stations to exercise restraint, and listen carefully on 80, 40 and 20 metres for any stations low down in the noise before using these bands. You may be interfering with emergency communications.

BERYL weakened as it moved towards Mexico, where it was classified as a Category Two hurricane. Still bad enough!

And in Cape Town, Michael ZS1MJT, our Regional Director has announced that Disaster Risk Management has asked HAMNET members to be on standby this weekend, as Level Six warnings were issued for severe weather today Sunday in the peninsula and along the Southern Cape coast. We ran an hourly net on 7110 kHz from yesterday afternoon the 6^th July, starting at 15h00 and interfering with the rugby until 19h00!

Ahead of this weather, the previous cold front brought icy conditions with it, likely to bring snowfalls over the mountainous regions of the Western Cape, the Eastern Cape, and extending into parts of the Northern Cape and Free State. Definitely time to unpack your long-johns for later use.

In another of his very comprehensive reports about the Scottburgh to Brighton Surf Ski Marathon, Keith Lowes ZS5WFD, Regional Director for HAMNET KZN says that they could not have wished for better weather conditions last Sunday the 30th. There was a light South Westerly blowing, and surf conditions were less than 1 metre.

Race Control was managed by Deputy Provincial Director Duncan ZS5DGR and Jitesh ZS5JM situated in Athlone Park Amanzimtoti at the QTH of Steve ZS5SH.

A team of 17 Hamnet-KZN operators were deployed to manage the safety of the event over the 46Km route.  Roeloff ZS5RPC reported that twelve single ski’s started at “Scottburgh” at 06H30 followed by fourteen doubles at 07H00.

It was compulsory for all competitors to have the App “SafeTrx” active on their cellular phones secured in a waterproof pouch.  This was monitored by the NSRI for any emergency activation.  I am pleased to report that NO activations were received. Eight inflatable rescue boats (IRB’s) and two Jet Ski’s monitored the competitors from a safe distance to minimise the risk of exhaust fumes impacting the paddlers.  The IRB’s were in contact with each other with newly purchased vhf commercial radios.

Next stop was “Green Point” which was under the watchful eye of Assistant Provincial Director Sid ZS5AYC and his team of Louis ZS5LS and Craig ZS6CHT. “Umkomaas” was covered by Mark ZS5JE and Paul ZS5PAH; “Winkelspruit” saw Geoff ZS5AGM and Val ZS5VAL positioned on the upper level of the Surf Lifesaving Club, giving them a great vantage point to view the race. A compulsory check-in at “Amanzimtoti” was monitored by Ben ZS5BN with race numbers being relayed to him from a rescue boat off-shore at a marker buoy.

Two single and two doubles started the short course (23Km) from Amanzimtoti at 08H00. “Windy Corner” in Athlone Park was covered by Wayne ZS5WAY. “Dakota Beach” Isipingo saw Shaun ZS5SM and Kathy ZS5OL keeping a good look-out.

It is safe to say that the busiest position was that of Rob ZS5ROB at the Bluff “V Cutting” who had his hands full reporting descriptions of ski’s passing his position to the Finish at “Brighton Beach” which was under the control of Provincial Director Keith ZS5WFD and Deon ZS5DD.

All communications were on 2 metres, using 145.550 Simplex with operators making use of portable masts with either directional or vertical antennas.

The winner of the Long Race – Double Ski – finished in 3 Hr 38 minutes whilst the first Single Ski finished in 4 Hr 09 minutes.

The race officials extended a sincere vote of thanks to HAMNET KZN for our valuable assistance in once again ensuring the successful running of the event.

Thank you Keith for ensuring that HAMNET KZN’s flag continues to fly high!

Indy100.com reports this week that scientists have just identified mysterious shapes flying above the Earth but, they say, don’t worry, this doesn’t mean that aliens are about to strike.

Using an imaging instrument called the Global-scale Observations of the Limb and Disk (GOLD), the experts uncovered strange X and C shapes, which have been cropping up in surprising places at surprising times.

The researchers found the structures dancing around the ionosphere – the area where Earth’s atmosphere meets space – and say that the discovery could help improve radio communications and space weather forecasts.

The ionosphere – which sits roughly 80 to 644 kilometres above the planet’s surface – becomes electrically charged as sunlight strikes it over the course of the day. This creates plasma bands of charged particles that are further influenced by Earth’s magnetic field, as Science Alert notes. And it is these bubbles of plasma that form the X and C shapes that have been observed.

This study and the GOLD data serve as further proof of how innovations in scientific research and technology are helping us to discover more about Earth and the Universe as a whole.

Astrophysicist Jeffrey Klenzing from NASA’s Goddard Space Flight Centre, who wasn’t directly involved in the study, pointed out: “The fact that we have very different shapes of bubbles this close together tells us that the dynamics of the atmosphere are more complex than we expected.”

With apologies for my gravelly voice, this is Dave Reece ZS1DFR reporting for HAMNET in South Africa.

In a summation of the activities over the ARRL Field Day weekend, the ARRL letter reports it to have been a successful event, despite severe weather and extreme temperatures impacting much of the country. Social media posted hundreds of photos and stories from the US, and 2200 logs had been received at the ARRL by Wednesday evening.

As an example of the type of report in their local press, The Northwest Ohio VHF Amateur Radio Society (NOVARS) set up their equipment near McComb for a day of intensive practice and community engagement.

Evan Hartman, a key member of the NOVARS club, took the time to speak about the event and its significance. Hartman explained that Field Day is not only a chance for amateur radio operators to showcase their skills but also a crucial exercise in preparing for real-world emergencies.

The NOVARS setup near McComb was impressive, featuring a range of antennas, transceivers, and portable power sources. Club members worked in shifts, ensuring continuous operation and communication with other Field Day participants across North America. The event served as a friendly competition, with clubs earning points based on the number of successful contacts they made, the variety of methods used, and the difficulty of the setups.

Hartman also emphasized the importance in welcoming new people to the amateur radio community and talked about resources available to get that first “ham radio” license.

The camaraderie among the NOVARS members was palpable on Saturday as they worked together to solve technical challenges and improve their setup throughout the day. Despite the intense focus on the technical aspects, there was also a strong sense of community spirit, with operators sharing stories, tips, and encouragement.

Local residents were invited to visit the NOVARS site to learn more about amateur radio. Many took the opportunity to see the equipment in action and understand the critical role that these enthusiasts play in times of crisis.

Field Day 2024 proved to be a successful event for NOVARS and the broader amateur radio community. With numerous contacts made and valuable experience gained, the event reinforced the importance of amateur radio operators and their role in emergency preparedness.

Thanks to wfin.com/local-news for these extracts from their article.

Meanwhile, in England, The Halifax and District Amateur Radio Society (HADARS) once again played a crucial role in ensuring the smooth operation of the Cragg Challenge 2024. This event, which includes a series of physically demanding challenges, takes place on the infamous 8km climb, renowned as the longest continuous climb in England. The terrain presents significant communication challenges due to numerous blackout areas caused by the valleys and hills, making comprehensive communication coverage difficult.

HADARS, leveraging its years of experience, rose to the challenge once more. The society has a longstanding relationship with the Cragg Challenge, having supported the event for several years. Their involvement provides HADARS members with valuable air time on the amateur radio bands, allowing them to hone their communication skills in a real-world environment.

The primary role of HADARS during the event is multifaceted. They provide crucial support to motorcycle marshals and the ambulance service, ensuring that help can be dispatched quickly in case of emergencies. Additionally, HADARS is responsible for keeping event organizers updated with real-time information from the entire route. This real-time data is vital for the smooth running of the event, enabling organizers to make informed decisions swiftly.

To tackle the unique communication challenges posed by the Cragg Challenge, HADARS strategically placed checkpoints along the route. Moreover, HADARS operated a remote station at Mount Skip between Old town and the village of Midgley. This station offers a commanding view of the entire course, making it a pivotal part of the communication strategy. 

The society’s efforts not only support the safety and coordination of the event but also provide a valuable training ground for amateur radio operators, highlighting the practical importance of this engaging hobby.

Thanks to the Halifax Courier for that report.

Capetown.gov.za reports that The City’s Disaster Risk Management Centre (DRMC) successfully hosted the annual resilience programme for women and girls. The programme started last week and came to a close yesterday.

The Women & Girls Invisible Force of Resilience programme started on 18 June 2024 with 19 learners from a variety of schools attending.

The week long programme included learning about disaster management concepts such as disaster preparedness, how to identify hazards and how to be an emergency ambassador. 

The programme started off at the DRMC in Goodwood and moved to other venues for the remainder of the course.

Other topics and learning interventions covered during the programme included;

Early warning systems                                                                                              Neighbourhood resilience assessment                                                          Flood and fire mitigation                                                                              Plastic Pollution                                                                                          Impacts of Climate Change                                                                                     Waste management                                                                                          A Self-defence course                                                                                 Bullying in schools                                                                                                 Basic firefighting                                                                                                          First Aid  

(Apologies here for the formatting difficulties – I could not get the above section to behave)

The group also learnt valuable tips about disaster preparedness in the home, and that families should have a disaster preparedness plan, which includes how to take care of animals during a disaster. The South Africa Weather Service provided valuable insights on extreme weather events and early warning systems.

On Thursday, participants spent the day at the City’s Rondevlei nature reserve where they went on a hike and learned about the importance of biodiversity and ecosystems. The following day participants were put through their paces at the Smart Living Centre in Cape Town where they discussed climate change in the Western Cape, water saving and recycling, among others.

“I’m excited to see the level of interest and the willingness to learn. The knowledge and skills learnt during the programme will put participants in good stead one day to be better prepared to deal with real life disasters, but also to reduce the risks in their homes and communities. We hope that they will become ambassadors for disaster risk reduction and that they will share knowledge and increase awareness in their environment on the importance of resilience and preparedness,” said Mayoral Committee Member for Safety and Security, Alderman JP Smith.

Participants who completed the programme received certificates during a ceremony at the DRMC Auditorium in Goodwood on Saturday, 29 June 2024.

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

I am very relieved to realize that we are now past the winter solstice, and our days are starting to grow longer again. Not by very much, mind you. It will take another 3 or 4 days before our Cape Town days last longer than 9 hours and 54 minutes, but every day counts.

Extreme weather is being reported from the Middle East, where very high temperatures of up to 50 degrees Celsius have been experienced during this year’s Hajj pilgrimage to Mecca in Saudi Arabia. More than 1000 pilgrims have died during the extreme heat, and the weather shows no sign of abating.

Similar temperatures eastwards as far as India have also been experienced, with deaths due to heatstroke being reported, and these support the assertion of several aid organizations in America, that have appealed to FEMA to accept extreme heat as being equally as disastrous as floods and storms.

The first Tropical Cyclone of the American Hurricane season has reared its head, as storm ALBERTO passed the coast of Texas this weekend and arrived on Mexico’s coastline. States of disaster were declared in 51 of Texas’ counties as the storm passed by. Strong winds are accompanying the rain and Guatemala and Belize are also in the storm’s aim.

According to the UN, heavy rainfall and strong winds associated with ALBERTO have impacted Guatemala, Nicaragua, Honduras and El Salvador. In addition, media report four fatalities in Nuevo León state, north-eastern Mexico.

The cyclone coincides with the ARRL Field Day weekend, so there will be lots of amateurs on the air, and perhaps helping to convey storm traffic to the National Hurricane Centre. Fortunately the storm is not very severe in strength at present, with wind speeds in the 90km/h range, but about 17 million people are in its path and will experience severe weather.

As you listen to this bulletin, Field Day will still be in progress, and the American Press has been loaded with articles about local radio clubs who will be operating and advertising the hobby. This is good, because it does make the general public aware of the sport and our capabilities, and perhaps encourage newcomers to take their exams and earn a call sign.

The ARRL for example reports that a dozen New Hampshire Amateur Radio Emergency Service (ARES) operators from the Mount Washington Valley ARES group and the Central New Hampshire ARES group, as well as a number of out-of-state ARES volunteers, again provided emergency radio communications at the Delta Dental Mount Washington Road Race on June the 15th.

Fourteen hundred participants ran up the mountain into a region of infamous wind chill and low visibility.

“We were there to keep our eyes open for any runners having physical difficulties, or medical issues,” said Skip Camejo, AC1LC, Public Information Coordinator for the ARRL New Hampshire Section and Public Information Officer for the New Hampshire ARES.

“This could have been done with cell phones, of course, but you can’t count on having a good signal on Mount Washington. That’s why the radio operators will be back for the August bike race up the mountain,” added Camejo.

The ARES help is also considered to be preparation for ARRL Field Day, this weekend, when more than 35,000 radio amateurs gather with their clubs, groups, or simply friends to operate from remote public locations.

Techxplore.com is reporting this week that, successfully to complete missions in dynamic and unstructured real-world environments, mobile robots should be able to adapt their actions in real-time to avoid collisions with nearby objects, people or animals.

Most existing approaches to prevent robot collisions work by creating accurate maps of the environment a robot is navigating and then planning the best trajectories to safely reach a desired location, beforehand.

Many previously proposed robot navigation techniques have achieved promising results in simulation. However, they often did not perform as well in real-world environments, particularly those that are unpredictable and rapidly changing over time.

Researchers at the University of California, San Diego recently introduced a new method that could enhance the navigation of mobile robots in dynamic and unstructured environments.

This method, introduced in a paper posted to the arXiv preprint server, has so far been successfully applied to the Jackal robot, a wheeled robotic system developed by ClearPath Robotics.

“Our recent paper addresses the critical need for safe autonomous navigation of mobile robots in complex, unknown and dynamic environments, while considering the limited sensing and computational resources available on-board,” Kehan Long, co-author of the paper, told TechXplore.

“While previous research has made significant advances using techniques such as artificial potential fields, navigation functions, and control barrier functions, many of those methods rely on constructing an accurate map of the environment.”

Building maps of dynamic environments in real-time can be challenging, particularly if these environments rapidly change over time. The key objective of the recent study by Long and his colleagues was to develop a new method that can guarantee the safety of mobile robots in these changing environments, directly leveraging data collected by a robot’s on-board sensors instead of reconstructing precise maps of the environment.

“Our novel method for safe mobile robot navigation introduces a distributionally robust control barrier function (DR-CBF) formulation,” Long explained.

“The core concept is directly to incorporate the robot’s noisy range sensor measurements (e.g., from LiDAR) into the control optimization as safety constraints, rather than first constructing an accurate map. By employing rigorous theories from distributionally robust optimization, we can robustly account for uncertainties in both sensing and the dynamic environment.”

The mobile robot navigation method developed by Long and his colleagues has various advantages over other approaches introduced over the past few years. Most notably, it can guarantee the safe operation of robots, preventing them from colliding with objects, while only requiring limited computational resources.

“A distinctive feature of our method is that it ensures safe navigation by directly utilizing recent sensor data in determining the control input, enabling the robot to swiftly adapt to environmental changes,” Long said.

“The practical implications of our work are significant. By enabling the development of reliable mobile robots with reduced computational requirements, our approach has the potential to lower the cost of building robots, making them more accessible for a wide range of applications.”

To test their method, Long and his colleagues applied it to the ClearPath Jackal, a wheeled weatherproof robot, which was equipped with a LiDAR sensor. Their findings were encouraging, demonstrating the effectiveness and versatility of their approach in both indoor and outdoor dynamic settings.

“In our future research, we plan to extend our methodology to more complex robotic systems, such as legged robots and humanoids,” Long added. “Our ultimate goal is to develop safe and capable robots that can navigate and interact in any environment while providing robust safety guarantees.”

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

Next weekend sees the ARRL Field Day event, during which individuals, groups and ham radio clubs set up off-grid radio stations, and practise making contacts in conditions similar to disasters, locally and around the world.

It is a 24 hour event, taking place on 22^nd and 23^rd June, and, depending on band conditions, calls for a contact may be audible in South Africa, on all HF ham bands, So if you are listening to your radio, and hear an increased volume of HF traffic next weekend, join in if you can, and give the American Hams some contacts.

The Daily Maverick reports that the combination of the devastating tornado that struck the North Coast of KZN, and the severe rainfall in the Eastern Cape, and snowfalls of the Free State the week before led to the National Disaster Management Centre (NDMC) classifying the severe weather events in the Eastern Cape, Free State and KwaZulu-Natal as a “national disaster”. 

Last week’s floods, strong winds, tornadoes and snowfalls resulted in devastation across the three provinces and caused deaths, injuries, significant property damage, extensive damage to infrastructure and environmental degradation. The damage is estimated at R1.3 billion, with the eThekwini metro accounting for more than R490 million.

Head of the National Disaster Management Centre Dr Elias Sithole said the scale of the incidents had surpassed the capacity of the affected communities to manage the disaster using their resources, and as such, the centre had classified the situation as a national disaster due to its impact on at least three provinces, as per Section 23(6) of the Disaster Management Act.

This signifies a formal recognition from the government that the events pose a significant threat to health, public safety or the environment which municipal and provincial governments cannot address on their own.

The primary responsibility for coordinating and managing this disaster now falls under the national executive which will use legislation and contingency plans to deal with the crisis.

Meanwhile, foxweather.com has announced that NASA rolled out a new program to use what it learns from space to help organizations respond to hurricanes, floods, heat waves and other weather-driven events on Earth. 

The U.S. space agency continues to use data from its more than a dozen Earth-observing satellites to help government agencies like FEMA respond to disasters, but on Thursday, NASA announced its Disaster Response Coordination System (DRCS), making its resources available in one place for anyone to access. 

“The idea is to close that last mile between what we know within the science community and the community of people who can put that science to use to inform decisions they have to make on the ground every day,” said Karen St. Germain, NASA Earth Sciences Division director. “Leaders at all levels, from neighborhoods to nations, need actionable information, and they needit where and when they need it.”

NASA’s DRCS Manager Joshua Barnes said the goal is to offer its full suite of Earth-observing resources to aid disaster response organizations worldwide. 

“This insight can be used to drive resource allocation decisions, take protective actions, and support the staging of disaster relief services, all using Earth Observation sciences,” Barnes said.

As an interesting aside in the discussion of how the world would survive disaster, iflscience.com speculates on the top five life forms that might survive an apocalyptic disaster.

Top of the list is our favourite microscopic creature, the Tardigrade. Tardigrades have been known to survive in just about every extreme environment Earth can throw at them. According to National Geographic, they are the “most indestructible animal on Earth”. They can claw their way through sand dunes, survive being frozen, and even live at high altitudes. 

Next on the list is the humble Cockroach which survived the asteroid impact that wiped out the dinosaurs, so they’ve got a pretty good chance of surviving the next global catastrophic event. 

Part of the reason for their success is both their size and their dietary habits. These flat-bodied insects can squeeze themselves into tiny crevices other critters can’t reach for protection, including inside soil. Plus, rather than relying on one type of food source, they will pretty much consume anything even if it isn’t technically food.

Depending on the conditions of the disaster, some animals could actually benefit from a global crisis. Vultures, for example, may also be able to survive something like a zombie apocalypse and with plenty of undead carrion around, could even thrive. They even have specially adapted stomachs with acid capable of digesting some pretty nasty bacteria, so potentially would be able to stomach some zombie guts. So vultures are awarded third position.

In the sea, we should not overlook the family of about 500 species of Shark. They are known to have lived through both World Wars and nuclear weapons tests and the evidence is right there in their eyes, where radiocarbon dating shows their age.  Sharks have also been around on Earth since before trees, and before Saturn had rings, so there’s a good chance at least one of the species of shark would survive. 

 The wildcard entry at number five is the Emperor Penguin. Emperor penguins can survive some of the most brutal cold temperature extremes the Antarctic can throw at them, including wind speeds of 200 kilometres per hour and temperatures of −50°C. They can also survive several weeks without eating by living off fat reserves. They occupy some of the most remote areas on Earth and therefore could be able to avoid zombies or disease spread by simple logistics. 

Interesting to note that the ultimate apex predator, the human being, features nowhere on this list!

This is Dave Reece ZS1DFR, not expecting to survive the next apocalyptic disaster, and reporting for HAMNET in South Africa.

A summary of the severe weather South Africa experienced in the Eastern Cape and KwaZulu-Natal, and issued by GDACS on Friday says that, following the heavy rainfall, strong winds and snowfall that affected the Eastern Cape and the KwaZulu-Natal provinces in eastern South Africa, on 1-3 June and caused floods, the number of casualties and damage has increased.

As of 6^th June, according to media reports, 22 people died, of whom 11 were in Eastern Cape and 11 in Durban area in KwaZulu-Natal, 55 people have been injured, 120 people have been displaced in three temporary shelters, more than 2,000 people have been evacuated in Nelson Mandela Bay Municipality. In addition, several houses and schools have been damaged.

Over the 48 hours to Today (Sunday), more rainfall was still forecast over western and southern South Africa, and drier conditions expected in the eastern provinces

Meanwhile, volcanic eruptions are being experienced in Philippines and heavy rainfall and flooding in Vietnam, Sri Lanka, Indonesia, China, Brazil and Germany.

Reporting on the ISUZU Ironman 70.3 event held in Durban on 2^nd June 2024, Keith ZS5WFD of HAMNET KZN reports a lovely cool start to the morning which saw 7 Hamnet KZN members deployed on the 90Km Bike Course between Suncoast Casino and Umdloti/M4 Freeway intersection.  A total of 1155 athletes and 34 teams entered for the event. 

Our primary objectives were to ensure cyclists safety by reporting unauthorised private vehicles on the route/road closures, medical emergencies, requests for bike maintenance and withdrawals. 

Joint Operations Centre (JOC) was situated opposite the old Natal Command HQ and manned by Provincial Director Keith Lowes ZS5WFD. Wayne ZS5WAY was positioned at the Penalty Tent 1 at M4/Umdloti, Ben ZS5BN was at the M4/Umhlanga off-ramp, Terry ZS5TB was at Penalty Tent 2 in Suncoast Casino parking area and Deon ZS5DD/Troy ZS5TWJ were at M4/Sandile Thusi at the turnaround (called Argyle Rd in the old street name terms)  Communications were all on 145.550 Simplex . Keith was using the 3-element dual band satellite antenna produced by AMSAT-SA, which was mounted on a telescopic mast.

The temperature recorded at 12H50 outside the JOC in Durban by Event Safety Officer Andre Botha was 28.8°C.

Keith was pleased to report that no serious incidents occurred and offers his thanks to those members that assisted on the day.

Their next event will be the Scottburgh to Brighton Paddle Ski Race on Saturday 29^th June 2024.

Thanks Keith for the reportage. Look forward to hearing from you after the 29^th of June!

Insideradio.com says in a report issued on 5^th June that The National Oceanic and Atmospheric Administration forecasts the upcoming hurricane season, which officially began June 1, will be among the most active in recent years. It is not just radio that is gearing up. So too is the Federal Communications Commission, where the focus in recent months has been on improving communications during disasters.

New FCC rules that took effect in May require wireless providers to share communications outages with the FCC and first responders and emergency management personnel at the federal, state and local level. Carriers must also develop roaming agreements with their rivals and agree on sharing physical assets to reduce the impact of wireless outages and support faster service restoration during emergencies. The Public Safety and Homeland Security Bureau announced the guidelines Tuesday for how states can request an activation of what is known as the Mandatory Disaster Response Initiative.

“After each hurricane, we examine what worked, what didn’t work, and what lessons we can apply to improve access to communications during future disasters,” FCC Chair Jessica Rosenworcel said in a statement. “That led us to adopt the new Mandatory Disaster Response Initiative, which requires wireless providers to collaborate during disasters so that people can stay connected when they most need it.

“During crises, the importance of staying connected takes on additional urgency,” Rosenworcel said. “And the Commission is continuing to do its part to improve communications reliability and resiliency for first responders and consumers.”

A report from news.sky.com notes that, when Maureen Sweeney gave her weather report on 3 June 1944, little did she know it would be central to thousands of troops successfully landing in Normandy – an event that went on to change the course of the Second World War.

“Please check, please repeat.” A frantic telephone call from a woman with a cut-glass English accent took Maureen Sweeney by surprise.

A short time earlier, the Irish postmistress had filed her hourly weather report: “Force six wind and a rapidly falling barometer.”

It was her 21st birthday but she and her soon-to-be husband Ted, keepers of the Blacksod Lighthouse, had their job to do.

Their son Vincent recalls: “My mother said, ‘oh my God, were my readings wrong?'” They were not wrong, but they had caused alarm for those planning the imminent D-Day landings.

Some 5,000 ships and 11,000 aircraft had transported 156,000 Allied troops in readiness for the beachfront offensive at Normandy. But there was one thing UK, US and Canadian commanders had no control over – the weather on 5 June, the date they had earmarked for invasion.

It is small and unremarkable in appearance, but the lighthouse at Blacksod Point in County Mayo was about to claim its place in history. Maureen’s son, Vincent, who is the current lighthouse attendant, explains: “We have the first gaze into the Atlantic.

“Any weather that is coming in will come in over us.

“But this depression, with northwest winds, was coming in directly over Blacksod, down through the UK and into the Channel.

“That would have hit Normandy in about five hours, so it was critical.”

Despite Ireland’s neutrality during the Second World War, it continued to supply weather forecasts to Britain under an agreement in place since independence.

Maureen never imagined for a moment that the fate of tens of thousands of Allied troops hung on her readings.

Her report on 3 June indicated a cold front lying halfway across Ireland and moving rapidly south-eastwards, towards Normandy.

Had the plan gone ahead, Allied troops would have faced catastrophe, trying to steer boats through rough water and scramble on to the beach in driving rain.

Maureen’s weather warning, checked and double-checked by Ted, persuaded those in charge to postpone by a day.

In the early hours of 5^th June, at General Eisenhower’s morning briefing, another report from Blacksod confirmed that the cold front had passed.

A loud cheer went up in the room, the long-awaited weather clearance had arrived and he gave the order for Operation Overlord to proceed.

And that, friends, is why D-Day took place on the very day my sister, who celebrated her 80^th birthday this past Thursday, was born, and not a day earlier!

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

I have to start this bulletin with reference to the disastrous landslide in the remote highlands of Papua New Guinea on Friday the 24^th May. A mass of boulders, earth and splintered trees devastated the village of Yambali when a limestone mountainside sheared away that Friday.

The blanket of debris has become more unstable with recent rain and streams trapped between the ground and rubble, said Serhan Aktoprak, chief of the International Organisation for Migration’s mission in Papua New Guinea.

Papua New Guinea’s government has told the UN it thinks more than 2,000 people were buried in the rubble.

“We are hearing suggestions that another landslide can happen and maybe 8,000 people need to be evacuated,” Mr Aktoprak told the Associated Press.

“This is a major concern. The movement of the land, the debris, is causing a serious risk, and overall the total number of people that may be affected might be 6,000 or more,” he said.

That includes villagers whose source of clean drinking water has been buried and subsistence farmers who lost their vegetable gardens.

“If this debris mass is not stopped, if it continues moving, it can gain speed and further wipe out other communities and villages further down,” Mr Aktoprak said.

A UN statement later tallied the affected population at 7,849, including people who might need to be evacuated or relocated. The UN said 42% of those people were younger than 16 years old.

“My biggest fear at the moment is corpses that are decaying,… water is flowing and this is going to pose serious health risks in relation to contagious diseases,” Mr Aktoprak said.

The warning comes as geotechnical experts and heavy earth-moving equipment are expected to reach the site soon.

The Papua New Guinea government on Sunday officially asked the United Nations for additional help and to co-ordinate contributions from individual nations.

An Australian disaster response team arrived on Tuesday in Papua New Guinea, which is Australia’s nearest neighbour. The team includes a geohazard assessment team and drones to help map the site.

Heartbroken and frustrated Yambali resident Evit Kambu thanked those who were trying to find her missing relatives in the rubble.

“I have 18 of my family members buried under the debris and soil that I’m standing on,” she told Australian Broadcasting Corp through an interpreter.

“But I can’t retrieve the bodies, so I’m standing here helplessly.”

Australian deputy prime minister Richard Marles said an Australian air force C-17 Globemaster, a four-engine transport jet capable of carrying 77 tons of cargo, was already bringing supplies from Australia to Papua New Guinea’s capital, Port Moresby.

Two smaller Australian air force turboprop transport planes were already at Port Moresby, which is 370 miles south-east of the devastated village.

Papua New Guinea is a diverse, developing nation with 800 languages and 10 million people who are mostly subsistence farmers.

After our building collapse in George last month, I’m sure we can easily imagine the trauma and suffering experienced by local survivors who don’t have any news of loved ones.

Nigel Rotherham ZS6RN has sent me a very complete report with tons of pictures of the annual Gauteng Scouting Kon-Tiki event, held between 17^th and 19^th May 2024 at Arrowe Park. I am going to have to prune the report significantly to fit it in to this bulletin.

He notes that close on 4,000 individuals (including HAMNET Gauteng members) participated in one way or another at the annual Gauteng Scouting Kon-Tiki event. The theme for this year’s event was “Ship Wrecked”.

Kon-Tiki is a competition where Scout Troops build a raft from drums, rope and poles using pioneering and other Scouting skills. In the Western Cape and Gauteng Kon-Tiki events, a patrol or team stays on the raft for 24 hours and completes various challenges while other Scouts who assisted in raft construction take part in “fringe” events on shore while the raft is afloat. Cub and Meerkat activities also take place as part of the overall Kon-Tiki experience.

Nigel notes that scouts built 47 rafts in total on Friday afternoon, and 1200 participants slept over that night, completing the projects early Saturday morning before launching that day, witnessed in total by about 3700 people. All rafts had launched by 15h30, with a 100% flotation success, and about 376 scouts slept on the water on the rafts that night. A campfire for 800 remaining land scouts was made that Saturday evening.

Hamnet Gauteng participation consisted of providing support for Kon-Tiki staff in the form of technical assistance for camp wide communications using the 433Mhz licence free band and based at the central JOC, which served as home for all the various ‘services’ in attendance.

The Scouts have their own stock of licence free hand-helds of which about 25 were deployed to the many staff, from the camp chief down, including those with water based responsibilities and roving ‘judges’.

Hamnet Gauteng also deployed one of their disaster communications units (i.e. multiple radios in a ‘GoBox’) as a means for members to ‘play radio’ and demonstrate the hobby to anyone passing by who showed interest. The JOC was located adjacent to the parade ground in the Info Tent which could not be missed being that it was a large white marque!

As with all ‘public service’ events that Hamnet attend, a key benefit of participation is the opportunity to test our skills and readiness of equipment. Kon-Tiki 2024 was no different and after deploying the UHF portable repeater on the Friday evening, it was found to be faulty… Rather have the failure now than in a real world disaster situation.

From set-up on Friday afternoon until breaking camp on Sunday, Hamnet Gauteng again enjoyed the greatest hobby on earth, being of service to others and also in the public eye.

Thanks go to the HAMNET Event Coordinators Brian (ZS6YZ) and Leon (ZS6LMG) plus team members Channette (ZS6CAC), Johan (ZS6DMX), Hannas (ZS6EMS), Andre (ZS6HE), Anja (ZS6SJC), Wim (ZS6WIM) and Maud, Lizette (ZS6ZET), Pro Ethnos International Fire and Rescue and of course Nigel (ZS6RN) during the weekend.

Nigel has sent a selection of very good photos to Anette ZR6D for inclusion on the HAMNET – South African Radio League – Emergency Communication Network Facebook Page. Thank you for the very comprehensive report, Nigel.

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

Kenya is again the victim of a tropical cyclone, this one called IALY. Heavy rainfall, strong wind and storm surge connected to the passage of the tropical cyclone IALY over the western Indian Ocean have been affecting the coastal area of Kenya over the last 48 hours, causing a number of severe weather related incidents, mainly due to the strong wind and storm surge that have resulted in casualties and damage.

Media report, as of 23 May, two fatalities and six injured people across the Kilifi county, south-eastern Kenya. In addition, media also report damages to infrastructure across the mentioned Kilifi county and the neighbouring Mombasa county.

Over the next 48 hours, more heavy rainfall with locally very heavy rainfall is still forecasted over the coastal area of Kenya.

The ARRL reports in its weekly newsletter that the 2024 National Convention at Dayton’s Hamvention was a huge success.

In Groves, Texas, officers were sent to a home on Wednesday, May 8, 2024, where police were told that four or five masked men were attempting to break in to a home, according to a news release. 

After officers found that the home had indeed been invaded, they spotted two of the suspects in a nearby field and arrested them following a brief foot chase.

Officers searched the suspects and found a radio “jamming device” in a backpack that they believe was being used during the burglary, according to the release.

Jamming radio signals is against federal law, according to the FCC website.

“Federal law prohibits the operation, marketing, or sale of any type of jamming equipment that interferes with authorized radio communications, including cellular and Personal Communication Services (PCS), police radar, and Global Positioning Systems (GPS),” according to the FCC.

I wonder whether would-be burglars in this country have become this sophisticated yet…

Newsonair.gov.in reports from India of a pioneering move towards reinforcing disaster communication capabilities, in which the Nagaland State Disaster Management Authority (NSDMA) has embarked on a ground-breaking initiative in collaboration with Open Source Classes for Amateur Radio India (OSCAR INDIA). Towards this, the NSDMA conducted a comprehensive mock drill exercise utilizing amateur radio technology on May 9.

This marks a significant milestone as the first-of-its-kind effort in enhancing alternative communication methods during emergencies. The state is also preparing to be the first disaster management authority in the country to enter into HAM Radio Technology for emergency communication systems.

Joint Chief Executive Officer of NSDMA, Johnny Ruangmei during a press briefing held at Nagaland Civil Secretariat Kohima today, informed that a mock drill was conducted which was also a first of its kind using HAM Radio technology, stating that it was a good lesson learned.

Phys.org is reporting this weekend of a potential forward leap in battery charging technology.

Imagine if your dead laptop or phone (or handheld radio) could charge in a minute or if an electric car could be fully powered in 10 minutes.

While not possible yet, new research by a team of CU Boulder scientists could potentially lead to such advances.

Published today in the Proceedings of the National Academy of Sciences, researchers in Ankur Gupta’s lab discovered how tiny charged particles, called ions, move within a complex network of minuscule pores. The breakthrough could lead to the development of more efficient energy storage devices, such as supercapacitors, said Gupta, an assistant professor of chemical and biological engineering.

“Given the critical role of energy in the future of the planet, I felt inspired to apply my chemical engineering knowledge to advancing energy storage devices,” Gupta said. “It felt like the topic was somewhat underexplored and, as such, the perfect opportunity.”

Gupta explained that several chemical engineering techniques are used to study flow in porous materials such as oil reservoirs and water filtration, but they have not been fully utilized in some energy storage systems.

The discovery is significant not only for storing energy in vehicles and electronic devices but also for power grids, where fluctuating energy demand requires efficient storage to avoid waste during periods of low demand and to ensure rapid supply during high demand.

Supercapacitors, energy storage devices that rely on ion accumulation in their pores, have rapid charging times and longer life spans compared to batteries.

“The primary appeal of supercapacitors lies in their speed,” Gupta said. “So how can we make their charging and release of energy faster? By the more efficient movement of ions.”

Their findings modify Kirchhoff’s law, which has governed current flow in electrical circuits since 1845 and is a staple in high school students’ science classes. Unlike electrons, ions move due to both electric fields and diffusion, and the researchers determined that their movements at pore intersections are different from what was described in Kirchhoff’s law.

Prior to the study, ion movements were only described in the literature in one straight pore. Through this research, ion movement in a complex network of thousands of interconnected pores can be simulated and predicted in a few minutes.

“That’s the leap of the work,” Gupta said. “We found the missing link.”

And I’m quite sure this Professor Gupta is not a previously unidentified brother of the Guptas we have come to know and distrust in this country.

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