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Ongeim’lTketau,EilMalk Island, Palau
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jellies
'JellyfishCentral'
Glidingglobesofgoldenjellies.That’swhatyou’llfindinOngeim’l Tketau.ThistinylakeonatinyislandinthePacificOceanisknownas"Jellyfish Central."
Overthousandsofyears,thejelliesherehavelostmostoftheirsting.It'ssafetoswimhere.Butifyoudo,beprepared.You’llhavetokeepupwiththejellies’busy schedule.
Inthemorning,thejelliesfloattotheeastsideofthelake.Intheafternoon,theybobbacktothewestside.Atbedtime,theyheadtowardthemiddle.Why?Tofollowthesunlight.Jelliesgettheirenergyfromalgaeintheirbodies—andthealgaegettheirenergyfromthesun.Jelliesavoidshadowsalongtheshoreline.That'swheretheirenemy,theanemone, lives.
What'sCooking?
Everyonelikesnicewarmwater.ButBoilingLakeontheislandofDominica,isextreme.Itboils,likeapotofsoupona stove.
Dominicaisbuiltbyvolcanoes.Andvolcanoesoftenhavefumaroles:searinghotholeswhereheatandgasescape.BoilingLakefillsafumarole.Nowonderit’sboiling.There’shotmagma underneath!
Gettingthererequiresatoughhike.Touristsscrambleupaslipperytrail.Theytrekthroughavalley,wheretheairsmellslikerotteneggs.Finally,theyreachacliffoverlookingBoilingLake.Look,butdon’tfall in!
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aviewfromaboveof Boiling Lake
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BoilingLake,
Dominica
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ameltwaterlakein Greenland
Thesemeltwaterlakesformedonanicebergin Greenland.
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DowntheDrain
It’ssummeronGreenland’svasticesheet.Lakesofmeltwaterdotthefrozensurfacelikebluejewels.Thedarkertheblue,thedeeperthe lake.
SomeofGreenland’smeltwaterlakesplayagameofnow-you-seeme,now-you-don’t.One,calledNorth Lake,sometimesdrainsallatonce.Oneyear,all45billionliters(12billiongallons)ofitdisappearedintwo hours!
Scientistsfiguredoutwhathappens.Astemperatureswarm,theiceshifts.Thatopenshugecracks.Thelakesdraindownthroughthecracks.It'slikesomeonepulledtheplugonabathtub.Thewaterrunsallthewaytothebaseoftheicesheet.Thenitflowstowardthesea.Whoknows?Maybeoneday,Greenland’swholeicesheetmightslipaway.Heretoday,gone tomorrow.