Sci­en­tists head to Hawaii to make the most of Big Is­land’s vol­canic ac­tiv­ity

Weekend Herald - - World - Sophia Yan and Mal­colm Rit­ter

Hawaii’s Ki­lauea vol­cano may be dis­rupt­ing life in par­adise with its bursts of ash and bright-orange lava, but it also has sci­en­tists wide-eyed, ea­ger to ad­vance what’s known about vol­canos.

The good news is: Vol­canos re­veal se­crets when they’re rum­bling, which means Ki­lauea is pro­duc­ing a bo­nanza of in­for­ma­tion.

While sci­en­tists mon­i­tored Big Is­land lava flows in 1955 and 1960, equip­ment then was far less so­phis­ti­cated. Given new technology, they can now gather and study an un­prece­dented vol­ume of data.

“Geo­phys­i­cal mon­i­tor­ing tech­niques that have come on­line in the last 20 years have now been de­ployed at Ki­lauea,” said Ge­orge Ber­gantz, pro­fes­sor of earth and space sci­ences at the Univer­sity of Wash­ing­ton. “We have this re­mark­able op­por­tu­nity . . . to see many more scales of be­hav­iour both pre­ced­ing and dur­ing this cur­rent vol­canic cri­sis.”

Start­ing May 3, Ki­lauea has foun­tained lava and flung ash and rocks from its sum­mit, de­stroy­ing hun­dreds of homes, clos­ing key high­ways and prompt­ing health warn­ings. Ki­lauea is one of five vol­canos that form the Big Is­land, and is a “shield” vol­cano — built up over time as lava flows layer on top of layer.

Tech­ni­cally speak­ing, it has been con­tin­u­ously erupt­ing since 1983. But the re­cent com­bi­na­tion of earth­quakes shak­ing the ground, steam-driven ex­plo­sions at the top, and lava creep­ing into a new area about 20km from the sum­mit rep­re­sents a de­par­ture from its be­hav­iour over the past 35 years, said Erik Klemetti, a vol­ca­nol­o­gist at Ohio’s Deni­son Univer­sity.

What’s hap­pen­ing now is a bit more like the Ki­lauea of nearly a cen­tury ago. In 1924, steam ex­plo­sions at the sum­mit lasted for more than two weeks.

Sci­en­tists are look­ing into what caused the change and whether this shift in the vol­cano’s magma plumb­ing sys­tem will be­come the new nor­mal.

Radar al­lows re­searchers to mea­sure the height of ash plumes shoot­ing from the sum­mit, even when they oc­cur at night.

Plume heights are an ef­fect of how much heat en­ergy is re­leased and the ex­plo­sion’s in­ten­sity.

“It’s one of the key fac­tors that dic­tates how far ash will be dis­persed,” said Charles Man­dev­ille, vol­cano haz­ards co-or­di­na­tor for the US Ge­o­log­i­cal Sur­vey. The other is where the winds are blow­ing. Such knowl­edge is use­ful in alert­ing the pub­lic.

Sci­en­tists can also mon­i­tor where gas is emerg­ing, as well as de­ter­mine its com­po­si­tion and vol­ume. They can even mea­sure the sub­tle rise and fall of the ground over a broad area and time — down to sec­onds — which sug­gests when and where magma is pool­ing un­der­ground.

Dis­cov­er­ing vari­a­tions or cor­re­la­tions be­tween past and present ac­tiv­ity pro­vides more clues on what’s hap­pen­ing. It also helps sci­en­tists un­der­stand past lava flows, an­tic­i­pate what could oc­cur next, and pin­point signs or pat­terns be­fore an erup­tion.

“You’re sort of ze­ro­ing in on finer and finer lev­els of de­tail into how the vol­cano works,” said Michael Poland, a US Ge­o­log­i­cal Sur­vey vol­ca­nol­o­gist. “The more stuff you put on the vol­cano to make mea­sure­ments, the more you re­alise there’s stuff go­ing on that you never knew.”

Bet­ter technology has also meant US Ge­o­log­i­cal Sur­vey sci­en­tists have been able to ac­cu­rately fore­cast Ki­lauea’s be­hav­iour as it sput­ters over Puna, the is­land’s most af­fected district.

“They’ve been spot on,” said Ja­nine Kripp­ner, a vol­ca­nol­o­gist at Con­cord Univer­sity in West Vir­ginia.

“It’s in­cred­i­ble — they’re look­ing at things hap­pen­ing be­low the sur­face, us­ing the mon­i­tor­ing equip­ment that they have, the knowl­edge they have of past erup­tions, and have been able to get peo­ple to not be in a deadly area.”

This week’s Gu­atemala erup­tion which killed more than 100 peo­ple shows that, un­for­tu­nately, this is not al­ways pos­si­ble, as na­ture can be un­pre­dictable.

Kripp­ner com­pared the Gu­atemala erup­tion to open­ing a can of soda af­ter shak­ing it vig­or­ously. Vol­canic gas un­der­neath cre­ated bub­bles that ex­panded, in­creas­ing pres­sure that blew magma apart when it reached the sur­face, spew­ing cooled lava rocks rang­ing from the size of sand grains to boul­ders.

Ex­plo­sions can be big­ger, or oc­cur dif­fer­ently, than ex­pected, and that presents a learn­ing op­por­tu­nity for sci­en­tists, who work on com­puter mod­els to map out ar­eas that may be at higher risk in the fu­ture.

“Look­ing at the footage after­ward, we can start to tease out how these things ac­tu­ally work,” Kripp­ner said, as it’s of­ten too dan­ger­ous for ex­perts to phys­i­cally get close to an erup­tion.

Vol­canic erup­tions hap­pen fairly reg­u­larly — as many as 60 oc­cur world­wide each year — but many are in iso­lated ar­eas, ac­cord­ing to the US Ge­o­log­i­cal Sur­vey.

Af­ter Ki­lauea’s 1924 sum­mit ex­plo­sions, the vol­cano en­tered a decade of pid­dly rum­blings, fol­lowed by 18 years of si­lence. Ex­perts say Ki­lauea may be head­ing to­ward years — even decades — of lit­tle or no ac­tiv­ity.

For now, vol­ca­nol­o­gists feel a “tremen­dous amount of re­spon­si­bil­ity” to learn as much as pos­si­ble from the vol­cano, Poland said.

“It’s com­ing at a great cost in terms of im­pact on the lives and liveli­hoods of so many peo­ple — we owe it to the peo­ple of Puna to make sure that we learn the lessons the vol­cano is teach­ing us,” Poland said. AP

Photo / AP

Lava from the east rift zone of the Ki­lauea Vol­cano has de­stroyed prop­er­ties as well as tide pools in the Kapoho Beach area.

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