Why some cancers are ‘born to be bad’

Cancer

A groundbreaking study has uncovered why some patients’ cancers are more deadly than others, despite appearing identical.

Francis Crick Institute scientists developed a way of analysing a cancer’s history to predict its future.

The study on kidney cancer patients showed some tumours were “born to be bad” while others never became aggressive and may not need treating.

Cancer Research UK says the study could help patients get the best care.

“We don’t really have tools to differentiate between those that need treatment and those that can be observed,” said researcher and cancer doctor Samra Turajlic.

One cancer could kill quickly while a patient with a seemingly identical cancer could live for decades after treatment.

It means uncertainty for both the patient and the doctor.

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Kidney cancer

KidneyImage copyrightCRICK INSTITUTE

It is most common in people in their 60s and 70s. Symptoms include:

  • Blood in your pee
  • Persistent pain in the lower back or side
  • Sometimes a lump or swelling in your side
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The work, published in three papers in the journal Cell, analysed kidney cancers in 100 patients.

The team at the Crick performed a sophisticated feat of genetics to work out the cancer’s history.

It works like a paternity or ancestry test on steroids.

As cancers grow and evolve, they become more mutated and, eventually, different parts of the tumour start to mutate in different ways.

Researchers take dozens of samples from different parts of the same tumour and then work out how closely related they are.

It allows scientists to piece together the evolutionary history of the whole tumour.

“That also tells us where the tumour might be heading as well,” said Dr Turajlic.

Chance to change care

The researchers were able to classify kidney cancer into one of three broad categories:

  • Born to be bad
  • Benign
  • Intermediate

The “born to be bad” tumours had rapid and extensive mutations and would grow so quickly they are likely to have spread round the body before they are even detected.

Surgery to remove the original tumour may delay the use of drugs that can slow the disease.

The benign tumours are at the complete opposite and are likely to grow so slowly they may never be a problem to patients and could just be monitored.

The intermediate tumours were likely to initially spread to just one other location in the body and could be treated with surgery.

Michael MalleyImage copyrightMICHAEL MALLEY

Michael Malley, 72, from London, took part in the trial at the Royal Marsden Hospital after being diagnosed with kidney cancer.

He said: “Clearly studies like these are really important for understanding how kidney cancer evolves over time, and I hope this one day leads to better treatments for patients like me.”

There is still the challenge of figuring out how best to tailor treatments to each tumour type, and even how to perform such tests in a hospital rather than a research lab.

The tools used in this study are being investigated in other cancers, including lung cancer.

Dr Turajlic says: “We’ve no doubt they will be applicable to other types of cancer.”

The studies also revealed that the earliest mutations that lead to kidney cancer were happening up to half a century before the cancer was detected.

Sir Harpal Kumar, the chief executive of Cancer Research UK, said the study was “groundbreaking”.

He added: “For years we’ve grappled with the fact that patients with seemingly very similar diagnoses nevertheless have very different outcomes.

“We’re learning from the history of these tumours to better predict the future.

“This is profoundly important because hopefully we can predict the path a cancer will take for each individual patient and that will drive us towards more personalised treatment.”

Secrets of the sea bed: Hunt for Stone Age site in North Sea

RV Belgica, file pic
Image captionThe RV Belgica: Exploring new frontiers under the North Sea

British and Belgian scientists are exploring the sea bed off Norfolk hoping to find evidence that Stone Age people lived there when it was still dry land.

In recent years, some trawler crews and researchers have found prehistoric animal bones and basic stone tools in North Sea sediment.

The team on the Belgian ship RV Belgica aims to map the Brown Bank area, a sand ridge about 30km (19 miles) long.

Mesolithic people are thought to have lived there in about 10,000-5,000BC.

“We suspect that the bank is on the edge of a large prehistoric lake, where you would expect settlements,” said Prof Vince Gaffney, an archaeologist at the University of Bradford.

Despite the prehistoric finds from the North Sea bed, so far no Mesolithic settlement has been found in that vast area, which flooded after 6,000BC as the Ice Age glaciers retreated.

Eventually the British Isles were cut off from the continent.

Sediment cores analysisImage copyrightVINCE GAFFNEY
Image captionSediment cores are collected in the quest for signs of Stone Age life

When the coast of continental Europe reached as far north as Norway, at the end of the Ice Age, the sea level was about 120m (394ft) lower than today.

“Areas under the North Sea now would have been the best to live in during the Mesolithic [period] – prime real estate, because the coastlines then had fish, birds, fresh water. But it is terra incognita,” Prof Gaffney said.

Brown Bank is about 100km (62 miles) from the Norfolk coast. It used to form part of a vast plain known as Doggerland.

North Sea map

For much of the Stone Age, before the Neolithic period, humans were nomadic hunter-gatherers.

But a Mesolithic settlement was discovered at Howick village, near the Northumberland coast – evidence that as long ago as 10,000BC some communities in Britain were no longer nomadic.

Read more on this topic:

Bradford archaeologists working with Prof Gaffney are aboard the oceanographic Belgian navy vessel with geologists from Belgium’s Ghent University and the Flanders Marine Institute.

Scientists have already mapped more than 45,000sq km (17,375sq miles) of prehistoric landscape under the North Sea, an area larger than the Netherlands, Prof Gaffney said.

But Brown Bank awaits detailed mapping, and then sediment core sampling, to look for DNA and other evidence of prehistoric life.

“The area is so large that complete cultures could be out there,” said Prof Gaffney, whose research project is called Lost Frontiers.

National Museum of Antiquities curator Luc Amkreutz identified this flint tool as a Mesolithic tranchet axe - the first such find from the North Sea. It was found by a Dutch fisherman in 1988Image copyrightRVO
Image captionThis was identified as a Mesolithic axe, found in the North Sea by a Dutch fisherman in 1988

Ghent University geologist Dr David Garcia Moreno said the Belgica team could collect seabed samples and video sites of interest, but the goal at this stage was to understand the underwater topography in detail. They will use sonar and seismic equipment for that.

“We want to understand the evolution of rivers that traversed the southern North Sea.

“We think there was a Palaeolithic lake and a large river system all the way from north-west Germany south through Brown Bank to the Dover Strait,” he said.

Map showing land around Britain and how it has been lost to the sea over the millenniaImage copyrightLOST FRONTIERS PROJECT
Image captionA map showing land around Britain and how it has been lost to the sea over the millennia

The research project, funded by the EU’s European Research Council, is growing. It still has at least two years to run.

The Belgica is quite cheap to hire and they are already looking forward to their next expedition, Dr Garcia said.

But Doggerland is not the only undersea territory yet to be mapped and explored for prehistoric remains.

Prof Gaffney says the Bering Strait, off Alaska, and Indonesia’s Sunda Strait are bigger. Who knows what prehistoric secrets lie there?

Map records UK’s small ups and downs

UK
Image captionThe map was produced from over 8 terabytes of radar data

The subtle warping of the land surface across the entire UK has been mapped in detail for the first time.

This view of changing topography was built from more than 2,000 radar images acquired by the European Union’s Sentinel-1 satellites.

It should prove an invaluable tool for policymakers, and for industries working on big infrastructure projects.

The map reveals areas of subsidence and uplift, some of which, like those above old mine workings, could be hazardous.

  • Play with the new map

Having detailed knowledge of their whereabouts, however, means the risks can now be properly assessed and mitigated.

For example, it can be seen how sections of the proposed route for the High Speed 2 rail link go across land that is still responding to the presence of coal pits at depth.

Some of the ground above disused tunnels is descending, while other locations are rebounding as water fills abandoned cavities.

The motion may be only millimetres per year, but it still needs to be recognised and factored into construction plans.

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HS2
Image captionHS2 route (black line), running from Birmingham to Leeds. Areas of subsidence (red/brown) and uplift (blue) are all related to abandoned coal mining

The deformation map was assembled using a technique called satellite interferometry.

By overlaying repeat radar pictures of the same location, it becomes possible to discern even the smallest changes in a scene.

Developed some 25 years ago, the approach always worked best where the spacecraft could see specific hard features time and time again.

These “persistent scatterers” would be objects like the corners of city buildings. But a few years ago scientists from the University of Nottingham found a way to also capture changes where “soft” features, such as vegetation, dominated the landscape.

Using this Intermittent Small Baseline Subset (ISBAS) analysis, it is now possible to frame a full picture of Britain that incorporates both urban and rural terrain.

Geomatic Ventures Limited (GVL) is the company that has been spun out from the university to commercialise the technology. Its chief technical officer, Dr Andy Sowter, told BBC News: “Persistent scattering interferometry relies on points that absolutely persist through all observations, but with the Sentinel satellites we now have so many images that we can use points that persist only perhaps through two-thirds of the observations.

“In the past this data would have been thrown away, but we’re able to be more selective, and that allows us to get at the full dynamic landscape for the first time.”

It has to be said, there are groups in the satellite interferometry community that are yet to be convinced by ISBAS. These teams believe that tracking change in vegetated areas is still a major challenge.

“While this initial map shows the potential power of Sentinel-1 for deformation monitoring on a nationwide-scale, many in the community have legitimate concerns about the reliability of these particular results, especially outside urban areas,” commented Prof Tim Wright from the University of Leeds.

London
Image captionTube extension: A large subsidence bowl (red/brown) just to the east of the Oval in London. The land level in this area has fallen by around 4cm over two years

The resolution of the map is about 90m. It will not show the movement in someone’s backyard, but it can notice the major deformation features.

The map will be scoured for widespread compaction of soils, landslides, eroding coastlines, and the subsidence over landfill and underground works.

For the public release of the map, GVL has highlighted some examples of interest.

These include a 500m-wide zone of depression at Kennington Park, part of the Northern Line tube extension in London. This subsidence is most probably related to the sinking of a shaft that was completed in November 2017.

In the far north of Scotland, GVL has been monitoring the peatlands of Caithness and Sutherland – the so-called Flow Country. Subsiding bogs release greenhouse gases and so the satellite imagery is a way to keep a check on the UK’s climate commitments.

“Probably the weirdest example we’ve come across is the 2cm per year uplift at a place called Willand in Devon. It’s a small place on the M5 motorway. We’ve spoken to the Environment Agency and the British Geological Survey, and right now we can’t explain it. We don’t know why it’s going up,” said Dr Sowter.

The map was put together over a two-year period from 2015 to 2017. But it is essentially now an operational product that could easily be updated every three months.

Scotland
Image captionNorthern Scotland’s Flow Country is a large, globally important peat bog and stores about 400 million tonnes of carbon – more than double the amount in all the UK’s forests

What makes this kind of offering possible is the avalanche of data being delivered from orbit by the EU’s Sentinel satellite series. Six spacecraft have so far been launched to image the Earth in a variety of ways, not just radar. A further 14 are already funded to fly.

All the data is deliberately free and open so that outfits such as GVL can exploit it and innovate new business applications.

Dr Josef Aschbacher is the director of Earth observation at the European Space Agency, which procures and manages the Sentinels for the EU.

Speaking here at the European Geosciences Union (EGU) General Assembly in Vienna, Austria, he projected an explosion of data in the years ahead.

“Today we are producing 14 terabytes of data from the Sentinels alone. We are producing more data from our satellites than all the images and videos being uploaded to Facebook every day,” he told BBC News.

He said his agency expected to be archiving some 100 petabytes of data by 2026 – all of it available to drive new services such as deformation mapping.

Global shipping in ‘historic’ climate deal

Container ship

The global shipping industry has for the first time agreed to cut its emissions of greenhouse gases.

The move comes after talks all week at the International Maritime Organization (IMO) in London.

Shippings has previously been excluded from climate agreements, but under the deal, emissions will be reduced by 50% by 2050 compared to 2008 levels.

One minister from a Pacific island state described the agreement as “history in the making”.

Shipping generates roughly the same quantity of greenhouse gas as Germany and, if it were accounted for as a nation, would rank as the world’s sixth biggest emitter.

Like aviation, it had been excluded from climate negotiations because it is an international activity while both the Kyoto Protocol and the Paris Agreement involved national pledges to reduce greenhouse gases.

 

The United States, Saudi Arabia, Brazil and a few other countries had not wanted to see a target for cutting shipping emissions at all.

By contrast the European Union, including Britain, and small island states had pushed for a cut of 70-100%.

So the deal for a 50% reduction is a compromise which some argue is unrealistic while others say does not far enough.

Kitack Lim, secretary-general of the International Maritime Organization, who had chaired the controversial talks, said: “This initial strategy is not a final statement but a key starting point.”

The tiny Pacific nation of the Marshall Islands had opened the conference with a plea for action.

Aerial photo of a container shipImage copyrightAFP

Although it has the world’s second largest register of shipping, it had warned that failure to achieve deep cuts would threaten the country’s survival as global warming raises sea levels.

As the talks concluded, the nation’s environment minister David Paul said: “To get to this point has been hard, very hard. And it has involved compromises by all countries. Not least by vulnerable island nations like my own who wanted something, far, far more ambitious than this one.”

Mr Paul added: “This is history in the making… if a country like the Marshall Islands, a country that is very vulnerable to climate change, and particularly depends on international shipping, can endorse this deal, there is no credible excuse for anybody else to hold back.”

Laurent Parente, the ambassador of Vanuatu, also a Pacific island nation, was not satisfied but hoped the deal would lead to tougher action in future.

“It is the best we could do and is therefore what this delegation will support as the initial strategy that we have no doubt will evolve to higher ambitions in the near future.”

By contrast, the head of the US delegation to the talks, Jeffrey Lantz, made clear his country’s opposition to the deal.

“We do not support the establishment of an absolute reduction target at this time,” he said.

IMO talks
“In addition, we note that achieving significant emissions reductions, in the international shipping sector, would depend on technological innovation and further improvements in energy efficiency.”

Mr Lantz reiterated that the US, under President Trump, has announced its withdrawal from the Paris Agreement on climate change.

He also criticised the way the IMO had handled the talks, describing it as “unacceptable and not befitting this esteemed organisation.”

But a clear majority of the conference was in favour of action.

The UK’s shipping minister, Nusrat Ghani, described the agreement as ” a watershed moment with the industry showing it is willing to play its part in protecting the planet”.

The move will send a signal through the industry that rapid innovation is now needed.

Ships may have to operate more slowly to burn less fuel. New designs for vessels will be more streamlined and engines will have to be cleaner, maybe powered by hydrogen or batteries, or even by the wind.

Rolls-Royce and Boeing invest in UK space engine

Reaction Engines Limited (REL), the UK company developing a revolutionary aerospace engine, has announced investments from both Boeing and Rolls-Royce.

REL, based at Culham in Oxfordshire, is working on a propulsion system that is part jet engine, part rocket engine.

The company believes it will transform the space launch market and usher in hypersonic travel around the Earth.

The new investments amount to £26.5m.

Included in this sum are contributions from Baillie Gifford Asset Management and Woodford Investment Management.

It lifts the total capital raised in the past three years to about £100m. The British government has already put in £60m. BAE Systems initially injected £20m in 2015 and has invested new funds in this latest financial round.

“Rolls-Royce and Boeing – these are really big names, and it’s fantastic to be in this position,” said REL CEO Mark Thomas.

“Rolls are super-positive about the technology. They want us to be independent and innovative, and to push our technology as hard as possible. And Boeing – that’s amazing. They are the world’s biggest aerospace company, have decades of expertise and future plans that, for us I’m sure, will be really exciting,” he told BBC News.

Pre-cooler
Image captionPre-cooler development was subject to an independent technical audit from the European Space Agency

REL is developing what it calls the Sabre engine. This power plant is designed to push a vehicle from a standing start all the way to orbit in a single step.

It would work like a conventional jet engine up to about Mach 5.5 (5.5 times the speed of sound) before then transitioning to a rocket mode for the rest of the ascent.

Key technologies include a compact pre-cooler heat-exchanger that can take an incoming airstream of over 1,000C and cool it to -150C in less than 1/100th of a second. This would permit Sabre to use oxygen direct from the atmosphere for combustion instead of carrying it in a tank with the weight penalty that implies.

Although Sabre is usually talked about in the context of an orbiting spaceplane, it could also be fitted to a vehicle that flies at very high speed from point to point on the Earth’s surface.

This is an application that clearly interests Boeing, whose investment arm, HorizonX Ventures, is driving the tie-up in what is its first investment in a UK-based company.

“As Reaction Engines unlocks advanced propulsion that could change the future of air and space travel, we expect to leverage their revolutionary technology to support Boeing’s pursuit of hypersonic flight,” said HorizonX vice president, Steve Nordlund.

Test centre
Image captionREL should get the keys to its future test facility at Westcott in the summer

Those who have followed the REL story over the years will be aware that Rolls-Royce is not really a newcomer to the project. The aero-engine giant was involved in Sabre’s precursor years – a spaceplane concept back in the 1980s known as Hotol.

When that hit technical difficulties, Rolls-Royce let its interest go, as did British Aerospace. Both are now back, the latter in its current guise as BAE Systems.

“We are delighted to become a strategic investor in Reaction Engines Limited, an innovative UK company that is helping push the boundaries of aviation technology,” Rolls’ CTO Paul Stein said in a statement.

“We look forward to working with REL and assisting with the development of their technology, and we plan to incorporate this technology into our own future products.”

REL is approaching important demonstration milestones.

In Colorado this summer, it will begin further testing of the pre-cooler technology, confronting it with conditions that simulate the very hot airstreams encountered when vehicles move at hypersonic speeds.

This will be done under contract with the US Defense Advanced Research Projects Agency (DARPA).

Concept vehicle
Image captionSabre engines could be fitted to reusable flight vehicles in the next decade

Also this summer, REL should take control of its new test facility in the UK at Westcott in Buckinghamshire. It is here that the company will mount a demonstration in 2020 of the full Sabre cycle.

Assuming this goes well, REL would then look to put the technology on some kind of flight vehicle.

The company is expanding fast with more than 160 staff at its Culham HQ. The new investments will allow it to continue the recruitment.

“The team here is outstanding. We have some of the most talented engineers I’ve ever worked with, a high percentage of whom are women engineers; and we have a great apprenticeship programme. It feels like we’re a good-news story and I want to keep it that way,” said Mark Thomas.

Isolated lakes found beneath Canadian ice sheet

hed new light on icy worlds in our Solar System.

High in the Canadian Arctic, two subglacial bodies of water have been spotted beneath over 500 metres of ice.

The water has an estimated maximum temperature of -10.5C, and would need to be very salty to avoid freezing.

There are thought to be similar cold, saline conditions in the subsurface ocean of Jupiter’s moon Europa, yet also the potential to host life.

The findings, from a team led by the University of Alberta, have been published in Science Advances.

Satellite map of the Devon ice cap, showing the location of Devon island in the Canadian Arctic and two long lakes in the middle of the ice sheet
Image captionAt 1,200m – 1,700m above sea level, the lakes sit in long basins in a mountain range

A Canadian first

The two lakes appeared in a radar survey of the Devon Ice Cap, which sits on Devon Island, in Canada’s northern Nunavut territory.

“I was super surprised, and a little bit puzzled,” Anja Rutishauser, the study’s lead author, said of the discovery. “I was definitely not looking for subglacial lakes.”

View from a plane window - the wing is visible to the right. A mountain range with a series of flat, snow-covered valleys in betweenImage copyrightGREGORY NG

Although water systems beneath large ice sheets are being found to be increasingly common, Devon Island’s ice cap was thought to be frozen to the bedrock beneath.

These are the first subglacial lakes to be observed in the Canadian Arctic, and are estimated to cover areas of five and eight square kilometres respectively.

“It’s an amazing finding, and one that I really wasn’t expecting from the geophysical survey of this small ice cap,” commented Prof Martin Siegert from Imperial College London, who was not involved in the study.

“To my knowledge, this is a unique lake system. Of the [more than] 400 subglacial lakes in Antarctica, all of them are thought to comprise fresh water. Hence, whatever might be living in it may also be unique,” he added.

A red aeroplane stationary on a landing strip. Ice field and mountains visible in the background.Image copyrightTOM RICHTER
Image captionSurveys were conducted using radar antennae, mounted to the wings of an aircraft

Life below zero

The water in the lakes is estimated to be five times as salty as seawater, allowing its freezing point to be lowered below that of fresh water.

Other subglacial lakes in Greenland and Antarctica contain fresh water, generated by melting at the base of the ice. Geothermal heat rises from the underlying rock, and is insulated by the thick ice sheet above.

The Canadian ice sheet is not thick enough to provide this insulation

Salt-rich water has been studied beneath Taylor Glacier in Antarctica’s McMurdo Dry Valleys, but this is supplied by an ancient marine water basin.

The mountainous location of these lakes places them above previous sea levels, and their salinity is derived from the high salt content of surrounding rock.

“It is interesting,” notes Prof Jemma Wadham from the University of Bristol, “that the more places we look, the more subglacial lakes we find. Just like in non-glacial environments, there could be a huge diversity of lake types and life habitat conditions, and one size does not fit all.”

A scientist with their back turned, operating radar equipment aboard an aircraftImage copyrightANJA RUTISHAUSER
Image captionRadar readings were taken across four years

A pocket of Europa

There are many answers researchers want to search for next. There may be an entire network of lakes in this region, beyond the two so far observed, and their size has yet to be determined.

However the potential for these environments to host life is a pressing question, as they may represent a largely isolated microbial habitat.

The study’s authors suggest the lakes may have been sealed off from surrounding environments for up to 120,000 years.

“The probability of life to exist in these systems is high, though the modelled temperatures might suggest that the biological activity would be severely limited due to the low temperature,” Dr Alison Murray of Nevada’s Desert Research Institute told BBC News.

From the cockpit of the plane: a chain of snowy mountains with an ice-filled valley in betweenImage copyrightGREGORY NG
Image captionView from the cockpit of a research flight

They may also provide a window to life beyond Earth.

Dr Claire Cousins from the University of St Andrews explains: “While the chemistry of these lakes may be somewhat different to ocean environments on icy moons such as Europa, their otherwise extreme conditions will help us understand the habitability of hypersaline sub-ice environments.”

While further radar surveys are next on the list, Anja Rutishauser and her colleagues hope to be able to drill into the lakes’ waters one day, to better understand any ecosystem within.

Such work could, Dr Murray says, provide “a key to understanding the life-supporting nature of such systems which may occur in the icy and ocean worlds of the Solar System and beyond.”

‘Tornado Alley’ and other things to know during tornado season

This photo provided by Johnny Tribble shows a damaged house after a tornado, Tribble said, passed the area in Ardmore, Ala., Monday, March 19, 2018. Severe storms that spawned tornadoes damaged homes and downed trees as they moved across the Southeast on Monday night. (Johnny Tribble via AP)

Severe thunderstorms ravaged across the southeast earlier this week, resulting in at least one confirmed tornado at Jacksonville State University in Alabama.

Now, parts of Florida and coastal communities in Georgia and the Carolinas are at risk for severe weather, which may include tornadoes.

Read on for a look at why tornadoes occur and what to do if you’re caught in one.

What is a tornado?

Essentially, a tornado is a column of air that spins at a high speed.

The column typically forms from a thunderstorm, stretching down and eventually reaching the ground below. When this happens, the column takes the shape of a funnel — also known as a funnel cloud, according to the Ready Campaign, a national public service campaign that helps Americans respond to natural and man-made disasters, among other things.

When do tornadoes typically occur?

“Peak tornado” season hits the South in March and ends around May, the Virginia Department of Transportation says on its website. The severe weather pattern usually makes its way north, with the majority of tornadoes hitting northern states over the summer.

“Half of tornadoes typically happen in May and June,” Harold Brooks, senior research scientist at the National Oceanic and Atmospheric Administration’s (NOAA) Severe Storms Laboratory, told AccuWeather in April 2017.

However, tornadoes tend to hit the Gulf coast earlier during the spring, NOAA explains on its website.

“But, remember, tornadoes can happen at any time of year. Tornadoes can also happen at any time of day or night, but most tornadoes occur between 4 to 9 p.m.,” NOAA adds.

Why do tornadoes occur and how do they form?

Most tornadoes form from supercells, also known as a rotating thunderstorm or a mesocyclone.

A supercell is typically a thunderstorm with the “winds already in motion,” according to National Geographic. It requires a combination of warm, moist air and cold, dry air — which are the “ingredients for a regular thunderstorm,” Brooks told the publication.

To put it simply, warm, moist air near the earth’s surface begins to rise, blowing in one direction at one speed. Subsequently, the cold air above is blowing in a different direction at a different speed. This creates a wind shear, which causes the air to rotate in a column. From here, if the air column gets caught in the updraft of a supercell, it causes the air to spin faster and create a funnel shape. The funnel of air becomes a tornado as it extends toward the earth and reaches the ground below.

It’s worth noting, however, that supercells are relatively rare. According to the National Weather Service (NWS), supercells are the least common type of thunderstorm.” Roughly one in a thousand storms become supercells. From there, only one in about six of those supercells will become a tornado, National Geographic reports.

But if they do form, “they have a high propensity to produce severe weather, including damaging winds, very large hail, and sometimes weak to violent tornadoes,” according to the NWS.

Where do tornadoes typically hit?

While tornadoes can form almost anywhere given the right conditions, they commonly touch down in Florida and an area of the U.S. called “tornado alley.”

Tornado alley, according to the National Centers for Environmental Information (NCEI), is a “nickname given to an area in the southern plains of the central United States that consistently experiences a high frequency of tornadoes each year.”

Tornado alley includes parts of central Texas, then moving into Great Plains states such as Oklahoma, Kansas, Nebraska, North Dakota and South Dakota. Parts of Iowa, Missouri and eastern Colorado are also considered part of tornado alley.

What can you do to protect yourself during a tornado?

The intensity of a tornado is measured using the Fujita scale, which ranges from an F0 to an F5. The latter is the most destructive and dangerous type of tornado. The winds from an F5 tornado can reach over 200 miles an hour.

To protect yourself from a tornado, it’s important to know the difference between a tornado watch and a tornado warning: a watch indicates a tornado could form, while a warning means a tornado has already been spotted, according to the Ready Campaign.

Some homes in Tornado-alley are equipped with Federal Emergency Management Agency (FEMA)-approved “safe rooms,” which, according to the organization, is a “hardened structure specifically designed to meet FEMA criteria and provide life-safety protection in extreme wind events, including tornadoes and hurricanes.”

However, if you are not able to reach a safe room during a tornado, it’s best to go to the lowest level of a structure, such as a basement. It is important to stay away from all windows, doors or anything else that leads outside, the Ready Campaign recommends. Wearing a helmet and placing blankets, pillows or even a mattress over your body may protect you from debris if a tornado hits your home or a nearby building.

What is an atmospheric river? Powerful storm to drench California

A powerful atmospheric river could bring multiple inches of rain to central and southern parts of California.

California residents, brace yourselves: an atmospheric river could bring multiple inches of rain to central and southern parts of the state over the next few days.

Read on for a look at the meteorological phenomeonon — and what to expect from the storm.

“Rivers in the sky”

An atmospheric river is a huge plume of subtropical moisture.

“Atmospheric rivers are relatively long, narrow regions in the atmosphere – like rivers in the sky – that transport most of the water vapor outside of the tropics,” the National Oceanic and Atmospheric Administration (NOAA) says.

“When the atmospheric rivers make landfall, they often release this water vapor in the form of rain or snow,” according to the agency.

They may also bring severe precipitation and destruction, though “most are weak systems that often provide beneficial rain or snow that is crucial to the water supply.”

The NOAA says atmospheric rivers are typically 250 to 375 miles in width.

What’s going on with California?

The National Weather Service (NWS) Los Angeles tweeted Tuesday that the atmospheric river event was happening.

“Heavier rain expected tonight into Thu with Flash Flood Watch in effect for recent burn areas,” it said.

The agency said in another tweet that coasts and valleys could get two to six inches of rain, with foothills and mountains getting five to 10 inches.

As many as 30,000 people have been ordered to leave communities by noon on the south coast of Santa Barbara County, where a Jan. 9 deluge unleashed deadly debris flows into Montecito.

Wreck of the USS Juneau, famous for the deaths of the 5 Sullivan brothers, discovered in Pacific

The wreck of the USS Juneau, which was sunk by a Japanese torpedo and lost 687 sailors in 1942, has been discovered by billionaire Paul Allen’s crew.

Five brothers from the Sullivan family were famously lost on the USS Juneau. Their story, which attracted widespread attention, was depicted in the 1944 movie “The Fighting Sullivans.” Two USS Navy ships have been named “The Sullivans” in memory of the brothers.

The brothers wanted to serve on the same ship, despite naval policies preventing siblings from serving together

The USS Juneau was found on St. Patrick’s Day resting on the seafloor near the Solomon Islands. An autonomous underwater vehicle (AUV) from the research vessel Petrel first identified the wreck using sonar on March 17. The following day, a remotely operated underwater vehicle (ROV) was deployed from Petrel to verify the wreckage, capturing video footage of the Juneau.

Juneau2

The prop of the USS Juneau resting on the seafloor. (Navigea, R/V Petrel)

“We certainly didn’t plan to find the Juneau on St. Patrick’s Day. The variables of these searches are just too great,” said Robert Kraft, director of subsea operations for Paul Allen, in a statement. “But finding the USS Juneau on Saint Patrick’s Day is an unexpected coincidence to the Sullivan brothers and all the service members who were lost 76 years ago.”

Juneau was sunk on Nov. 13 1942 during the Battle of Guadalcanal. When a second torpedo hit her port side, an explosion cut the ship in half, killing most of the crew. The light cruiser sank in just 30 seconds. Around 115 of Juneau’s crew are believed to have survived the sinking, including, possibly, two of the Sullivan brothers. However, with U.S. forces concerned about the risk of further Japanese attacks, rescue efforts did not take place until eight days later. Only 10 men were rescued from the water.

The first ship named after the brothers, USS The Sullivans (DD-537), was commissioned in 1943 and is now a museum ship in Buffalo. The second ship to bear the family name (DDG-68) is in active service as a guided missile destroyer.

Sullivans

The Sullivan brothers photographed on board the USS Juneau, 14 Feb. 1942 From left to right: Joseph, Francis, Albert, Madison and George Sullivan (Courtesy U.S. Naval History and Heritage Command)

“As the fifth commanding officer of USS The Sullivans (DDG 68), a ship named after five brothers, I am excited to hear that Allen and his team were able to locate the light cruiser USS Juneau (CL 52) that sunk during the Battle of Guadalcanal,” said Vice Adm. Rich Brown, commander, Naval Surface Forces, in a statement. “The story of the USS Juneau crew and Sullivan brothers epitomize the service and sacrifice of our nation’s greatest generation.”

Expeditions led by Microsoft co-founder Paul Allen have discovered a host of historic military shipwrecks, such as the USS Lexington, which was located earlier this month, 76 years after it was lost in the Battle of the Coral Sea.

INCREDIBLE IMAGES OFFER FIRST GLIMPSE OF SUNKEN WWII-ERA AIRCRAFT CARRIER

Juneau

The USS Juneau In New York Harbor, 11 Feb. 1942. (Courtesy the U.S. National Archives)

Last year Allen’s crew found the long-lost wreck of the USS Indianapolis in the Philippine Sea. The sinking of the Indianapolis, which delivered the Hiroshima bomb and is mentioned in the movie “Jaws,” in 1945 resulted in the greatest single loss of life at sea in the U.S. Navy’s history. Of 1,196 crew aboard the heavy cruiser, only 317 survived.

California mudslides: Where and why they happen

Parts of central and Southern California could be impacted by powerful mudslides this week, weather forecasters said, thanks to a massive atmospheric river that’s expected to hit the state late Tuesday.

An atmospheric river, or a huge plume of subtropical moisture, could result in up to 5 inches of rain in coastal areas and valleys, and up to 10 inches of rain in foothills and mountains.

As a precaution, authorities ordered Santa Barbara County residents who live near the same area that was ravaged in December by the Thomas Fire, the state’s largest wildfire on record, to evacuate on March 20.

So far, at least 30,000 people have been ordered to leave.

The powerful storm comes after some 21 people died from the mudslides that swept over parts of the state’s southern region in January, mainly in Montecito, Santa Barbara County — an area northwest of Los Angeles that’s home to celebrities such as Ellen DeGeneres, Rob Lowe and Oprah Winfrey, among others.

Several homes were destroyed from the mudslides, which were sparked after torrential rains caused flash flooding in the Santa Ynez Mountains. The flooding caused mud and debris to slide down from wildfire-charred hillsides that are stripped of vegetation, eventually reaching the communities below.

Here’s what you need to know about mudslides.

Why do mudslides occur?

A firefighter stands on the roof of a house submerged in mud and rocks Wednesday, Jan. 10, 2018, in Montecito, Calif. Anxious family members awaited word on loved ones Wednesday as rescue crews searched grimy debris and ruins for more than a dozen people missing after mudslides in Southern California destroyed houses, swept cars to the beach and left more than a dozen victims dead. (AP Photo/Marcio Jose Sanchez)

A firefighter stands on the roof of a house submerged in mud and rocks Wednesday, Jan. 10, 2018, in Montecito, Calif.  (The Associated Press)

Mudslides, also known as debris flows, are a type of landslide that can occur after a natural disaster, such as a wildfire. Debris flows often contain mud, rock and other materials.

“Human modification” of land can make certain slopes and steep areas “vulnerable to landslides during and after heavy rains,” according to the Center for Disease Control and Prevention, which estimates that roughly 25 to 50 people die each year in the United States because of land and mudslides.

But mudslides can also occur without a wildfire preceding it, according to Francis Rengers, a research geologist at the United States Geological Survey (USGS), the science agency for the Department of Interior.

In January, “you had a large amount of rain and a burn area that didn’t need much to get going in the first place,” Rengers said.

A few different factors contribute to debris flows in Southern California, David Peterson, a professor of forest ecology at the University of Washington, told Fox News.

The Thomas Fire, which burned more than 280,000 acres and primarily affected Ventura, Montecito, Carpinteria and Santa Barbara Counties, among others, removed “all of the living and dead vegetation that protected the soil beneath,” Peterson said. The land quickly eroded when there was no vegetation to hold it in place.

The fire was also hot enough to “cook out” the organic matter in the soil, which helps the earth to absorb water when it rains.

“When you have five or more inches of water in a day or two, it doesn’t buffer the impact of the rain on the soil,” he said, adding that the soil also became very hot from the wildfires. This results in the so-called “hydrophobic effect,” which causes the soil to repel water.

Different soil texture can also affect the severity of mudslides, Peterson said. As for the January’s incident, however, Peterson added that “the upper layer of soil got so saturated [by the rain] that it became like Jell-O and just flowed downhill.”

Where do they occur?

Mudslides typically occur in areas with steep hillsides, gullies and other narrow channels that make it easy for rain, mud and debris to flow through — much like the terrain in Southern California, Peterson said. These gullies and other passageways form over millions of years.

In the West, “the rains always come in the winter, flow downhill and create these big drainages,” he said.

While Peterson acknowledged the devastation that mudslides have caused, he said that the occurrence is a “natural phenomena.”

“Big mudslides are normal. This has happened for millions of years,” he said.

Is there anything that can be done to prevent or stop mudslides?

This aerial photo provided by the Santa Barbara County Fire Department shows mudflow and damage to homes in Montecito, Calif., Wednesday, Jan. 10, 2018. Anxious family members awaited word on loved ones Wednesday as rescue crews searched grimy debris and ruins for more than a dozen people missing after mudslides in Southern California on Tuesday destroyed over a 100 houses, swept cars to the beach and left more than a dozen victims dead.  (Matt Udkow/Santa Barbara County Fire Department via AP)

This aerial photo provided by the Santa Barbara County Fire Department shows mudflow and damage to homes in Montecito, Calif., Wednesday, Jan. 10, 2018  (Santa Barbara County Fire Department)

The short answer: no.

“There’s nothing to prevent the magnitude of these events,” Peterson said. While dams might catch some of the sediment, he said, the structures wouldn’t be of much use for a large mudslide.

It’s unclear if the Thomas Fire made the mudslides worse. Peterson suspects not. But Rengers said the USGS is continuing to research the phenomena.

“Basically, the really high rainfall rates are what controlled the really large response that we saw. And the damage inflicted by the debris flows is proportional to the rainfall,” Rengers said in January.

What can people do to protect themselves?

Peterson cautioned those who choose to live beneath steep hillsides in Southern California.

“There are many homes at the bottom of these steep drainages. But at some point mudslides will happen,” he said.

He explained that when people choose to build their homes at the bottom of these steep drainages, they “decide to take on the risk because they think it’s a low probability it [mudslides] will happen to them.”

Most of the stucco-style homes that are popular in California don’t have basements or subfloors — meaning they have relatively little defense against the powerful mudslides.

Since many of the stucco homes are placed on top of a cement slab, the soil from the mudslide weighs more than the house. The result? The homes become like “a little boat in the bathtub,” he said. “These are natural risks that people need to think about.”

Peterson said that most people would have better luck defending their home from a fire than a mudslide. In 2014, debris and mud from a mudslide in Oso, Washington, covered a square mile in roughly 20 seconds, Peterson said.

Rengers cautioned people who do have homes in these areas to “heed all evacuation warnings.”

“If they don’t evacuate and are stuck, they should try contacting local authorities,” he said.

In anticipation of mudslides in January, California authorities ordered evacuations beneath the burned areas of Santa Barbara, Ventura and Los Angeles Counties. But many people ignored the warning until it was too late. Ten to 15 percent of people in a mandatory evacuation area in Santa Barbara County heeded the warning.

In response, Santa Barbara County emergency authorities announced on Feb. 8 that the word “voluntary” will be replaced by new evacuation terminology such as “pre-evacuation advisory,” ”recommended evacuation warning” and “mandatory evacuation order” during future mudslides and wildfires.