JOHN: TONIGHT ON PBS NEWS WEEKEND, DEFENSE SECRETARY PETE HEGSETH DOUBLES DOWN ON ATTACKING ALLEGED DRUG BOATS, SAYING PRESIDENT TRUMP CAN TAKE MILITARY ACTION AS HE SEES FIT.

THEN, HOW SMALL PLUG-IN SOLAR PANELS THAT CAN BE MOUNTED ON BALCONIES AND WALLS ARE GAINING TRACTION AS A WAY TO CUT ELECTRICITY BILLS.

AND, THE LAND OF FIRE AND ICE -- SCIENTISTS ARE FLOCKING TO ICELAND TO SEE WHETHER MELTING GLACIERS COULD MEAN MORE INTENSE EARTHQUAKES AND VOLCANIC ERUPTIONS.

>> ICELAND IS ESSENTIALLY ONE OF THE BEST PLACES IN THE WORLD TO STUDY THIS.

IT'S A NATURAL LABORATORY BECAUSE WE HAVE BOTH VOLCANISM AND GLACIERS.

ANNOUNCER: MAJOR FUNDING FOR PBS NEWS WEEKEND HAS BEEN PROVIDED BY -- THE ONGOING SUPPORT OF THESE INDIVIDUALS AND INSTITUTIONS.

AND FRIENDS OF THE NEWS HOUR.

THIS PROGRAM WAS MADE POSSIBLE BY THE CONTRIBUTIONS TO YOUR PBS STATION FROM VIEWERS LIKE YOU.

THANK YOU.

OHN: GOOD EVENING, I'M JOHN YANG.

THE SHOCK WAVES FROM AN ALLEGED - - CONTENTIOUS SECOND STRAIGHT ON AN ALLEGED DRUG-SMUGGLING BOAT IN THE CARIBBEAN IN SEPTEMBER ARE STILL REVERBERATING SOME THREE MONTHS LATER.

THAT SECOND ATTACK CAME ABOUT A HALF-HOUR AFTER A FIRST STRIKE APPEARED TO HAVE DESTROYED MOST OF THE BOAT.

TODAY, LAWMAKERS WHO WERE SHOWN VIDEO OF THE ATTACKS OFFERED STARKLY DIFFERENT INTERPRETATIONS OF WHAT THEY SAW.

>> THE BOAT WAS ADRIFT.

IT WAS GOING WHERE THE CURRENT WAS GOING TO TAKE IT, AND THESE TWO WERE TRYING TO FIGURE OUT HOW TO SURVIVE.

>> THEY WERE NOT INCAPACITATED, THEY WERE NOT IN THE WATER, SURVIVING ONLY BECAUSE THEY HAD A LIFE JACKET OR HANGING TO A PLANK OF WOOD.

THEY WERE SITTING ON THAT BOAT, THEY WERE CLEARLY MOVING AROUND ON IT.

JOHN: AT A DEFENSE FORUM IN CALIFORNIA SATURDAY, DEFENSE SECRETARY PETE HEGSETH DEFENDED THE ACTION.

>> I FULLY SUPPORT THAT STRIKE.

I WOULD HAVE MADE THE SAME CALL MYSELF.

THOSE WHO WERE INVOLVED IN 20 YEARS OF CONFLICT IN IRAQ AND AFGHANISTAN OR ELSEWHE KNOW THAT RE-ATTACKS AND RESTRIKES OF COMBATANTS ON THE BATTLEFIELD HAPPEN OFTEN.

JOHN: HEGSETH WOULDN'T SAY IF THE VIDEO WOULD BE MADE PUBLIC, SAYING THAT THE QUESTION IS UNDER REVEIW.

- - UNDER REVIEW.

EVEN AS NEGOTIATORS SEEK TO END THE WAR IN UKRAINE, RUSSIA BOMBARDED THE COUNTRY WITH OVERNIGHT ATTACKS.

AT LEAST FOUR PEOPLE WERE KILLED AND NEARLY A DOZEN OTHERS INJURED.

IN FLORIDA, WHITE HOUSE SPECIAL ENVOY STEVE WITKOFF AND UKRAINIAN NATIONAL SECURITY OFFICIALS WRAPPED THREE DAYS OF TALKS THIS WEEKEND ABOUT PRESIDENT TRUMP'S PEACE PLAN.

AFTER THE ATTACK, UKRAINIAN PRESIDENT VOLODYMYR ZELENSKYY CALLED FOR MORE AIR DEFENSE SYSTEMS -- A REQUEST HE'S LIKELY TO REPEAT TOMORROW WHEN HE MEETS WITH EUROPEAN LEADERS.

A MASSIVE FIRE AT A POPULAR NIGHTCLUB IN INDIA HAS KILLED AT LEAST 25 PEOPLE, INCLUDING TOURISTS.

IT WAS IN NORTH GOA -- A POPULAR AREA FOR TOURISTS AND NIGHTLIFE.

LOCAL POLICE SAY IT WAS TOUCHED OFF WHEN A GAS CYLINDER EXPLODED.

OFFICIALS SAID SOME OF THE 100 PEOPLE ON THE DANCE FLOOR RUSHED INTO THE KITCHEN AND GOT TRAPPED ALONG WITH STAFF.

AUTHORITIES SAID THE CLUB VIOLATED FIRE SAFETY REGULATIONS, AND THAT ACTION WOULD BE TAKEN AGAINST CLUB MANAGEMENT AND OFFICIALS WHO ALLOWED IT TO OPERATE.

WITH THE GIFT GIVING SEASON JUST AROUND THE CORNER, SHOPPERS LOOKING FOR GOOD DEALS ARE GETTING SAVVIER -- BUT SO ARE HOLIDAY SCAMMERS.

ONE IN THREE AMERICANS SAY THEY'VE FALLEN PREY TO AN ONLINE SHOPPING SCAM.

JUST LAST YEAR, SCAMS INVOLVING ITEMS THAT WERE EITHER COUNTERFEIT OR NEVER DELIVERED COST PEOPLE MORE THAN $700 MILLION.

ALI ROGIN EXPLORES THESE SCAMS WITH ALISSA ABDULLAH, DEPUTY CHIEF SECURITY OFFICER FOR MASTERCARD.

>> THANK YOU SO MUCH FOR BEING HERE.

WHAT ARE SOME OF THE MOST COMMON HOLIDAY SCAMS PEOPLE SHOULD BE LOOKING OUT FOR?

>> THE MOST COMMON HOLIDAY SCAMS ARE THESE FLASHY ADS, BIG DISCOUNTS.

THOSE ARE THINGS YOU NEED TO THINK ABOUT.

ANOTHER COMMON HOLIDAY SCAM MAY BE CHARITABLE WEBSITES.

WE ARE IN A TIME WHEN PEOPLE ARE IN THE SEASON OF GIVING, YOU MIGHT WANT TO BE CAREFUL AND VERIFY THE WEBSITE, VERIFY THE CHARITY, AND MAKE SURE IT IS A VERIFY CHARITY BEFORE YOU DONATE.

ALI: WHAT CAN PEOPLE TRY TO MAKE SURE THOSE SHOPPING SITES AND CHARITY SITES ARE LEGITIMATE?

>> THE FIRST THING I TELL PEOPLE TO DO IS TAKE A BEAT.

TAKE A PAUSE, GO AND DO YOUR OWN RESEARCH ON THAT WEBSITE.

THE EASIEST THING TO DO.

THEN YOU CAN SAY, I WILL GO ON THE PLATFORM.

YOU NEED TO VERIFY THE PLATFORM.

SOMETIMES THE WEBSITE MAY LOOK GOOD, THE CHARITY MAY SOUND RIGHT, BUT THE PLATFORM IS A LITTLE SHAKY.

YOU NEED TO VERIFY ALL OF THOSE THINGS.

I LOOK AT THE URL TO MAKE SURE WORDS ARE SPELLED RIGHT.

IF YOU ARE GOING TO MAKE A PAYMENT, YOU WANT TO USE HTTPS.

THE S ON THE END OF HTTP MEANS SECURE.

WHEN I'M SENDING MONEY FROM MY COMPUTER TO ANOTHER PERSON, IT IS THROUGH A SECURE TUNNEL.

ALI: MASTERCARD PUT OUT A REPORT THAT SAID THAT NEARLY HALF OF TODAY'S CONSUMERS ARE LIKELY TO IGNORE THE RED FLAGS AND SOMETHING BEING A BIG FLASHY SALES IF THERE IS A REALLY REALLY LUCRATIVE DEAL BEHIND IT.

THEY MIGHT JUST PURCHASE THAT THING ANYWAY.

WHY IS THAT AND HOW SHOULD PEOPLE AVOID FALLING INTO THOSE TRAPS?

>> WE ALWAYS WANT TO GET THE BIG DEAL.

CYBER CRIMINALS KNOW THAT AS WELL.

WHEN THEY ARE THINKING ABOUT IT, THEY ARE TARGETING US WITH QR CODES, FLASHY, URGENT, YOU HAVE TO CLICK THIS LINK RIGHT NOW.

ACTUALLY, YOU DON'T HAVE TO CLICK THE LINK RIGHT NOW.

IF YOU MISS THAT DEAL AT ONE STORE, YOU WILL FIND IT AT NOTHER.

I ALWAYS TELL PEOPLE, TAKE A PAUSE, VERIFY.

IT IS OK.

THAT IS THE SUGGESTION THAT GOES PAST HOLIDAY SEASON.

ALI: HOW LUCRATIVE ARE THESE SCAMS TO SCAMMERS?

>> VERY VERY LUCRATIVE.

WE ARE TALKING ABOUT A BIG, BIG BUSINESS GLOBALLY.

YOU THINK ABOUT IT FROM A GOOD PERSON'S PERSPECTIVE OR THE CYBERSECURITY PERSPECTIVE, WE HAVE TO GET IT RIGHT EVERY SINGLE TIME.

THE SCAMMER HAS TO GET IT RIGHT MAYBE ONCE OR TWICE.

THEN YOU HAVE A BIG PAYCHECK COMING IN.

WE TAKE NOTE OF THAT.

WE USE A LOT OF TOOLS OF THE BACKGROUND TO MAKE SURE WE ARE FIGHTING, NOT JUST FIGHTING AND DETECTING BUT ALSO PREVENTING.

WE KNOW NOW WITH AI HOW WE CAN PREVENT FRAUDULENT TRANSACTIONS AND PREVENT A CARD BEING COMPROMISED BEFORE YOU KNOW IT IS COMPROMISED.

IT IS A TRICKY TIME NOW, BUT WE HAVE TOOLS IN PLACE TO HELP.

ALI: WITHOUT ASKING YOU TO REVEAL TOO MUCH ABOUT SOURCES, WHAT IS A COMPANY LIKE MASTERCARD DOING TO KEEP CUSTOMERS SAFE?

>> BEFORE, WE WOULD TAKE A CERTAIN AMOUNT OF DATA.

WE WOULD TRIANGULATE THAT DATA AND FROM THAT INFORMATION SAYING THIS APPEARS TO BE FRAUDULENT.

NOW AI HAS GIVEN US LEAPS AND BOUNDS.

WE HAVE BEEN USING AI FOR THE PAST TWO DECADES.

MANY THINK ABOUT THREAT INTELLIGENCE, LOOKING AT AT PATTERNS AND PATTERN RECOGNITION AND KNOWING, IS ALI REALLY IN BAHRAIN MAKING THIS PURCHASE?

NO, SHE ISN'T.

THOSE ARE THE THINGS WE LOOK AT BUT NOW WE HAVE MORE DATA POINTS ABOUT YOU, YOUR TRANSACTIONS, ALL THE INFORMATION, STORES, YOUR PATTERNS, YOUR HABITS THAT WE CAN PUT TOGETHER IN A MATTER OF SECONDS TO HELP MAKE A DECISION ON WHETHER THE TRANSACTION IS FRAUDULENT OR REAL.

ALI: WHAT IS YOUR ADVICE TO PEOPLE WHO MIGHT BE UNFAMILIAR WITH THE DEGREE TO WHICH AI IS PLAYING A ROLE IN THEIR PURCHASES?

> PEOPLE ARE ALREADY I THINK USING AI NOW IN ORDER TO THINK THROUGH, WHAT DO I WANT TO BUY MY SPOUSE?

WHEN YOU THINK ABOUT IT FROM THE OTHER PERSPECTIVE, AI IS BEING USED TO TARGET PEOPLE, AI IS BEING USED TO FAKE NOT JUST WEBSITES, BUT YOUR VOICE, YOUR DIALECT, YOUR INTONATION, YOUR EMAILS.

THERE IS A BALANCE.

WE ARE USING IT FOR GOOD, FOR OUR LEVEL OF CONVENIENCE, BUT THEN THE ADVERSARY IS ALSO USING IT ON THEIR SIDE.

LUCKILY WE'VE GOT TOOLS IN PLACE, AND CONVERSATIONS LIKE THIS TO REMIND PEOPLE, SLOW DOWN, WATCH, TURN ON YOUR NOTIFICATION, KNOW WHAT IS COMING OUT OF YOUR ACCOUNT SO YOU KNOW YOU CAN STOP THINGS ON YOUR OWN AS WELL.

ALI: ALISSA ABDULLAH, DEPUTY CHIEF SECURITY OFFICER FOR MASTERCARD, THANK YOU SO MUCH.

JOHN: STILL TO COME ON PBS NEWS WEEKEND.

THE GROWING POPULARITY OF PLUG-IN SOLAR PANELS ACROSS THE UNITED STATES.

AND, AS THE WORLD'S GLACIERS MELT, SCIENTISTS INVESTIGATE WHETHER THAT WILL LEAD TO STRONGER EARTHQUAKES AND MORE VIOLENT VOLCANIC ERUPTIONS.

ANNOUNCER: THIS IS PBS NEWS WEEKEND FROM THE DAVID M. RUBENSTEIN STUDIO AT WETA IN WASHINGTON, HOME OF THE PBS NEWS HOUR, WEEKNIGHTS ON PBS.

JOHN: FOR YEARS, SOLAR POWER AT HOME WAS MOSTLY LIMITED TO PEOPLE WHO OWNED THEIR ROOFTOPS AND COULD AFFORD THE STEEP UPFRONT COSTS.

BUT THAT IS CHANGING.

A NEW GENERATION OF SMALL, AFFORDABLE SYSTEMS, OFTEN CALLED PLUG-IN SOLAR, ARE MAKING CLEAN ENERGY MORE ACCESSIBLE.

THE TECHNOLOGY IS ALREADY WIDESPREAD IN GERMANY AND THE MOVEMENT IS GAINING MOMENTUM IN THE UNITED STATES.

OUR REPORT IS FROM LAURA KLIVANS OF PBS MEMBER STATION KQED IN SAN FRANCISCO.

>> AGNES CHAN IS A RETIRED TEACHER IN BERKELEY, CALIFORNIA.

SHE WANTED TO INSTALL SOLAR PANELS ON HER HOME, BUT WAS LIMITED BY HER FIXED INCOME BUDGET.

>>I EVEN CONSULTED MY ROOFER, BUT THERE'S NO WAY THAT I CAN AFFORD THAT.

>> SO SHE FOUND A CHEAPER WORK AROUND AND IS ONE OF THE NEWEST ADOPTERS OF PLUG-IN SOLAR.

SHE HOPES TO REIN IN BILLS THAT RUN INTO THE HUNDREDS, EVEN WITH A THERMOSTAT SET TO 60.

>> IT'S A GREAT HOUSE I HAVE LIVED IN FOR OVER 35 YEARS, BUT THERE'S NO WAY TO INSULATE IT.

SO I'M SHIVERING IN MY OWN HOUSE.

>> INSTEAD OF TENS OF THOUSANDS OF DOLLARS FOR ROOFTOP SOLAR, THIS COST $400 AND TOOK LESS THAN AN HOUR TO INSTALL.

>> THIS WILL SHOW ME HOW MUCH THE PANEL IS GENERATING.

>> RATHER THAN TAKING A DECADE OR SO TO PAY IT BACK, IT WILL LIKELY TAKE HER TWO TO THREE YEARS.

>> WE ARE SYSTEMATICALLY REMOVING THE BARRIERS.

EPORTER: THIS NONPROFIT BRINGS PLUG-IN SOLAR'S TO RENTALS, PEOPLE IN MULTIFAMILY HOUSING, AND OTHER AMERICANS SHUT OUT OF ROOFTOP SYSTEMS.

>> THESE THINGS ARE MODULAR, THEY ARE TINY, YOU CAN PUT THEM ABOUT ANYWHERE.

YOU CAN ADD AS TIME GOES ON.

IT IS A LESSON BIG UPFRONT INVESTMENT AT ONCE.

EPORTER: FROM PLUG-IN CARPORTS TO BALCONIES, ENTREPRENEURS ARE INVESTING IN THIS EMERGING MARKET.

>> NOW THAT YOU'VE SEEN THE POSSIBILITIES FOR INSTALLATIONS - - REPORTER: BUT THERE'S A MAJOR HURDLE TO WIDESPREAD ADOPTION.

IN MOST OF THE U.S., IT IS NOT LEGAL TO JUST SET UP THE SYSTEMS AND PLUG THEM IN AS ENVISIONED.

>> THE NEXT TOPIC ON THE AGENDA, SO CALLED PLUG-IN SOLAR.

REPORTER: AT A RECENT ONLINE FORUM HOSTED BY CALIFORNIA'S UTILITY REGULATORS, IAN HOFFMAN WHO WORKS FOR PG&E SAID CUSTOMERS MUST COMPLY WITH REGULATIONS AND PAY FEES AS IF THEY WERE SETTING UP A ROOFTOP YSTEM.

UTILITIES ASSAY THAT HELPS THEM MANAGE ENERGY SUPPLY AND DEMAND BUT PLUG-IN SOLAR ADVOCATES SAY THEIR SYSTEMS SHOULD HAVE A SIMPLER REGISTRATION PROCESS.

>> THE WORLD HEADQUARTERS OF BROOKS ENGINEERING.

REPORTER:REPORTER: WE ASK AN INDEPENDENT EXPERT TO WEIGH IN.

BILL BROOKS IS AN ELECTRICAL ENGINEER WHO SPECIALIZED IN SOLAR FOR 37 YEARS.

HE HELPS WRITE CALIFORNIA'S CODE THAT GOVERNS HOW SELECTOR NEXT TO THE GRID.

>> THERE'S 78 SOLAR PANELS.

I CALLED HIM A SOLAR GUARD.

REPORTER: HE SAYS THERE ARE ISKS.

>>>> IF THE PRODUCT DID NOT HAVE PROPER CERTIFICATIONS, THERE WOULD BE THE POSSIBILITY THAT SOMEBODY COULD ENERGIZE A DOWNED POWER LINE THAT COULD INJURE A LINEMAN.

REPORTER: BUT BROOKS SAYS THE BARRIERS CAN BE OVERCOME BY UPDATING EXISTING TOOLS.

>> THIS IS A MICRO-INVERTER AND THINGS LIKE PLUG-IN SOLAR.

IT HAS A CERTIFICATION.

AND WE HAVE THE NATIONAL ELECTRICAL CODE.

REPORTER: WHEN THESE SAFEGUARDS ARE IN PLACE, BROOKS DOES NOT SEE THE NEED FOR A LENGTHY OR COSTLY REGISTRATION.

AND HE SAYS INDEPENDENT ORGANIZATIONS ARE WORKING ON A SAFETY STANDARD FOR THE TECHNOLOGY.

BUT PLUG-IN SOLAR COMPANIES AND THEIR CUSTOMERS ARE NOT WAITING FOR REGULATORS.

BAY AREA RESIDENT JOE TENENBAUM CONSIDERED ROOFTOP SOLAR WHEN HE HAD RISING ELECTRICITY BILLS.

>> A GOOD AMOUNT OF SUNSHINE FROM EARLY ON.

REPORTER: BUT IT WOULD REQUIRE REPLACING THE ROOF, TOO.

AND COSTS QUICKLY BALLOONED.

>> AND WE DON'T OWN THIS HOUSE.

THIS IS MY PARENTS' HOME.

MY WIFE AND KIDS AND I MOVED IN WHEN MY MOM GOT SICK.

IT IS NOT FEASIBLE FOR THEM TO MAKE IT 100 THOUSAND DOLLAR INVESTMENT IN A ROOFTOP SYSTEM AND IT IS NOT EITHER FOR US.

REPORTER: TENENBAUM LIKES THE IDEA THAT THEY WOULD BE ABLE TO TAKE THEIR PANEL WITH THEM IF THEY MOVED.

FOR $1600, HE BOUGHT AN 800 WATT DIY KIT FOR -- AND HE LIKED HOW THEY BUILT SAFETY MEASURES INTO THEIR TECHNOLOGY.

THE COMPANY ALSO ADVISES CUSTOMERS TO REGISTER THEIR SYSTEMS.

THE PANELS WON'T POWER THE WHOLE HOUSE BUT WILL KEEP TENENBAUM'S REFRIGERATOR HUMMING AND SMALL APPLIANCES CHARGED.

HE EXPECTS TO SAVE 5% TO 10% ON HIS MONTHLY UTILITY BILL.

CRAFT FROM CO-FOUNDER AND BROTHERS MICHAEL AND STEPHEN SAY DEMAND FOR PLUG-IN SOLAR IS GROWING.

>> BASICALLY HERE IN CALIFORNIA, PEOPLE ARE TELLING US ABOUT THE TIME OF USE RATES THAT DOUBLE AS THEY COME HOME AND USE HOWARD.

THE SECOND -- USE POWER.

THE SECOND MOTIVATION IS THE GREEN REVOLUTION.

REPORTER: LEGISLATORS ACROSS THE COUNTRY ARE TAKING NOTE.

>> WE KNOW THEY ARE SAFE BECAUSE THEY'VE BEEN DOING THIS FOR FOUR YEARS NOW AND IT HAS WORKED OUT WELL.

REPORTER: EARLIER THIS YEAR, YOU TALK PAST THE FIRST LEGISLATION NATIONWIDE TO ALLOW PLUG-IN SOLAR WITH NO REGISTRATION WHEN CERTAIN SAFETY STANDARDS AND CODES ARE SET.

SIMILAR LEGISLATION IS IN THE WORKS AND SEVERAL OTHER STATES INCLUDING NEW YORK, NEW HAMPSHIRE, PENNSYLVANIA AND VERMONT.

>> MY PANEL IS PRODUCING 645 WATTS PER HOUR.

EPORTER: AS FOR AGNES CHAN IN CALIFORNIA, SHE IS HOPING TO STAY WARMER THIS WINTER.

>> I EXPECT TO BE COMFORTABLE INSTEAD OF SHIVERING IN MY OWN HOUSE, WEARING A DOWN JACKET AND A BLANKET TO WATCH TV.

REPORTER: EVEN IF EVERYONE IN THE U.S.

HAD THESE PANELS, PLUG-IN SOLAR COULD ONLY COVER A SLICE OF THE NATIONAL ENERGY DEMAND, BUT EXPERTS SAY EVERY BIT OF RENEWABLE ENERGY COMES.

>> BIG MOMENT HERE.

I'M VERY EXCITED ABOUT THIS NEW SYSTEM.

JUST ON BOXING IT FELT LIKE OPENING UP A GIFT.

>> WE HAVE SOLAR.

>> THAT'S ALL THERE IS TO IT.

REPORTER: FOR PBS NEWS WEEK AND, I'M LAURA CLIVE IN NORTHERN CALIFORNIA.

- - LAURA LIVANS IN NORTHERN CALIFORNIA.

JOHN: THE UNITED NATIONS DESIGNATED 2025 THE INTERNATIONAL YEAR OF GLACIER PRESERVATION.

AS THE EARTH GROWS WARMER, THE WORLD'S GLACIERS ARE MELTING.

IN ICELAND, AND ELSEWHERE AROUND THE GLOBE, SCIENTISTS FEAR THAT MELTING COULD BE SETTING OFF A TICKING TIME BOMB -- MORE FREQUENT AND STRONGER VOLCANIC ERUPTIONS AND EARTHQUAKES.

WILLIAM BRANGHAM HAS THIS ENCORE REPORT.

REPORTER: GETTING TO THE VOLCANIC CRATER CALLED VITI -- WHICH COMES FROM THE ICELANDIC WORD FOR HELL -- INVOLVES A BUMPY RIDE, AN ICY TREK, AND A STEEP DOWNWARD CLIMB.

>> THE GAS EMISSIONS ALONE CAN BE VERY DANGEROUS.

HERE, YOU'RE TAKING A GREATER RISK BECAUSE YOU'RE ACTUALLY IN AN OLD, PHREATIC EXPLOSIVE CRATER.

AND THIS IS A SITE OF ACTIVE DEGASSING.

WILLIAM: MICHELLE PARKS IS A VOLCANOLOGIST WITH THE ICELANDIC METEOROLOGICAL OFFICE.

SHE AND HER COLLEAGUES REGULARLY MONITOR THIS DEEP, CRATER LAKE, WHICH WAS CREATED YEARS AGO BY THE VOLCANO ASKJA.

ASKJA LAST ERUPTED IN 1961 BUT IT STARTED STIRRING AGAIN IN 2021 -- IT'S ONE OF THE MOST ACTIVE AND POTENTIALLY DANGEROUS VOLCANOES IN ICELAND.

SCIENTISTS FLOCK HERE FOR RESEARCH, AND THEY ARE ASKING AN INCREASINGLY CRUCIAL QUESTION.

AS THE GLACIERS THAT SIT ATOP THESE VOLCANOES MELT, WHICH IS DRIVEN IN PART BY A WARMING PLANET, WILL THAT SHRINKING ACCELERATE AND INTENSIFY VOLCANIC ERUPTIONS?

>> I THINK IT'S VERY LIKELY THAT WE WILL SEE FUTURE CHANGES BUT THE QUESTION, OF COURSE, IS WHEN WILL THIS START HAPPENING AND BY HOW MUCH WILL IT AFFECT VOLCANIC ACTIVITY?

WILLIAM: PARKS TAKES ACIDITY AND TEMPERATURE READINGS FROM THE BUBBLING, STEAMING, SULPHUROUS WATER OF THE CRATER LAKE.

A RISE IN EITHER FIGURE WOULD INDICATE THAT MORE GASES ARE PUSHING UP FROM BELOW, SUGGESTING THE VOLCANO IS MOVING CLOSER TO AN ERUPTION.

>> ASKJA IS MY FAVORITE VOLCANO IN ICELAND.

SO, I'VE BEEN COMING HERE EVERY YEAR SINCE 1990 TO FOLLOW WHAT THE VOLCANO IS DOING.

WILLIAM: FREYSTEINN SIGMUNDSSON IS A GEOPHYSICIST AT THE UNIVERSITY OF ICELAND.

EVERY YEAR, HE AND HIS COLLEAGUES TAKE PRECISE MEASUREMENTS OF THE LANDSCAPE AND THEY'RE FINDING THAT THE LAND IS SHIFTING CONSIDERABLY.

>> FOR MY DECADES OF STUDIES HERE, THE CHANGES OF THE GROUND HERE HAVE BEEN ON THE CENTIMETER SCALE.

BUT THEN SUDDENLY, WHEN THE UNREST BEGAN, WE HAVE HAD OVER 70 CENTIMETERS OF UPLIFT.

SO THAT'S A LOT.

THAT'S A BIG PRESSURE INCREASE.

WILLIAM: THAT BUILDING PRESSURE INDICATES THIS VOLCANO COULD ERUPT AT ANY MOMENT.

SCIENTISTS CAN'T RULE OUT THAT ONE DAY ASKJA COULD ERUPT WITH THE SAME FEROCITY THAT MOUNT SAINT HELENS DID IN 1980 IN WASHINGTON STATE.

IT WAS ONE OF THE MOST DRAMATIC ERUPTIONS IN RECORDED U.S.

HISTORY.

EARLIER THIS SUMMER, ASKJA HAD ONE WAS LARGE ENOUGH FOR PEOPLE TO FEEL.

BUT THOSE SMALL QUAKES, COMBINED WITH CHANGES IN THE TERRAIN, AS WELL AS WHAT'S HAPPENING WITH THE GLACIERS, HAVE RESEARCHERS CONCERNED ABOUT THE FUTURE.

>> SO WE'RE WORKING ON THIS ARGE PROJECT INVESTIGATING THE EFFECTS OF CLIMATE CHANGE AND THE ICE RETREAT ON FUTURE VOLCANIC AND SEISMIC ACTIVITY IN ICELAND.

WILLIAM: ICELAND HAS LONG BEEN KNOWN AS A LAND OF FIRE AND ICE.

EONS OF VOLCANIC ERUPTIONS SHAPED THIS WILD AND DRAMATIC LANDSCAPE.

BUT MILLIONS OF TOURISTS ALSO COME HERE TO SEE THE MAJESTIC BEAUTY OF ITS GLACIERS AND ICE FORMATIONS, UP CLOSE, HOPEFULLY BEFORE THEY DISAPPEAR.

AT HIS SUMMER HOUSE OVERLOOKING THE VATNAJOKULL ICE CAP, RAGNAR FRANK KRISTJANSSON HAS SEEN GLACIERS RETREATING WITH HIS OWN EYES.

>> IT WAS IN THE FIRST 15 YEARS, IT WAS A LITTLE BIT FORWARD, TEN METERS BACKWARD, NOTHING BIG CHANGES.

THE LAST 10 YEARS, IT IS GOING TO BE 100 METERS EACH YEAR.

IT'S ONE FOOTBALL FIELD.

WILLIAM: HE'S BEEN A GLACIER MONITOR FOR MORE THAN 25 YEARS , TRACKING THE RETREAT OF TWO LARGE GLACIERS NEARBY.

HIS DAUGHTER IRIS HAS ALSO SEEN THE SAME CHANGES OVER HER LIFETIME.

>> I HAVE SOMETIMES SAID TO PEOPLE, IT IS LIKE WATCHING YOUR FRIENDS DISAPPEAR AND HAVING A VERY ROUGH TIME.

AND WE LOOK AT THE GLACIERS OUT OF OUR KITCHEN WINDOW EVERY DAY.

I THINK LIKE OF COURSE, IT'S JUST DEVASTATING TO SEE LIKE LOOKING AT THE PHOTO ALBUMS AND SEEING LIKE, OH MY GOD, YOU KNOW, WHEN I WAS GROWING UP, THE GLACIERS WERE SO MUCH BIGGER.

>> I MEAN, ICELAND IS ESSENTIALLY ONE OF THE BEST PLACES IN THE WORLD TO STUDY THIS.

IT'S A NATURAL LABORATORY BECAUSE WE HAVE BOTH VOLCANISM AND GLACIERS.

WILLIAM: MICHELLE PARKS, ALONG WITH OTHER SCIENTISTS, ARE TESTING TO SEE IF THESE SHRINKING GLACIERS COULD TRIGGER MORE VOLCANIC ERUPTIONS.

ICE STILL COVERS NEARLY HALF OF ICELAND'S 34 ACTIVE VOLCANIC SYSTEMS.

BUT AS IT MELTS, IT LESSENS THE DOWNWARD PRESSURE ON THE EARTH'S THIN OUTER CRUST AND MUCH THICKER UNDERLYING MANTLE.

THAT ALLOWS THE EARTH TO REBOUND, AND THAT CHANGE IN PRESSURE SPURS VOLCANOES TO PRODUCE MORE MAGMA, SENDING IT IN DIFFERENT DIRECTIONS AND POTENTIALLY CREATING NEW FRACTURES UNDERNEATH.

WHILE IT'S TOO EARLY TO KNOW FOR SURE, THERE ARE POTENTIALLY GRAVE IMPLICATIONS FOR THE TENS OF MILLIONS OF PEOPLE WHO LIVE NEAR BOTH GLACIERS AND VOLCANOES AROUND THE WORLD.

A 2020 STUDY FOUND 245 VOLCANOES WITHIN THREE MILES OF A GLACIER, FROM THE ANDES, TO NORTH AMERICA'S CASCADES, TO PLACES LIKE THE KAMCHATKA PENINSULA IN RUSSIA, WHERE A MASSIVE 8.8 MAGNITUDE QUAKE STRUCK LAST MONTH.

SIX DIFFERENT VOLCANOES ERUPTED NEARBY -- THEY'D BEEN DORMANT SINCE THE 16TH CENTURY.

THE PENINSULA IS ALSO FAMOUS FOR ITS EXTENSIVE GLACIERS.

GIVEN THE SCALE OF THE THREAT, IN ICELAND, THEY'RE IN A RACE TO RESEARCH THEIR OWN RISKY FUTURE, AND POTENTIALLY HELP WARN OTHERS AROUND THE WORLD WHO FACE A SIMILAR THREAT.

FOR PBS NEWS WEEKEND, I'M WILLIAM BRANGHAM.

JOHN: THAT IS PBS NEWS WEEKEND FOR THIS SUNDAY.

I'M JOHN YANG.

FOR ALL OF MY COLLEAGUES, THANKS FOR JOINING US.

HAVE A GOOD WEEK.

ANNOUNCER: MAJOR FUNDING FOR PBS NEWS WEEKEND HAS BEEN PROVIDED BY -- >> IN 1995, TWO FRIENDS SET OUT TO MAKE WIRELESS COVERAGE ACCESSIBLE TO ALL.

WITH NO LONG-TERM CONTRACTS, NATIONWIDE COVERAGE AND 100% U.S.-BASED CUSTOMER SUPPORT, CONSUMER CELLULAR.

FREEDOM CALLS.

ANNOUNCER: THE ONGOING SUPPORT OF THESE INDIVIDUALS AND INSTITUTIONS.

THIS PROGRAM WAS MADE POSSIBLE BY CONTRIBUTIONS TO YOUR PBS STATION FROM VIEWERS LIKE YOU.

THANK YOU.

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