Laura Robinson: The secrets I find on the mysterious ocean floor
ローラ・ロビンソン: 神秘的な海底で私が出会う秘密
Dr. Laura Robinson's scientific mission is to document and understand the processes that govern climate. Full bio
Double-click the English transcript below to play the video.
of the ocean today.
of the ocean in the past.
サンゴの化石を使います
of deepwater corals.
of these corals behind me.
深海で採取されたもので
thousands of meters below the sea,
than the kinds of corals
サンゴとはかなり違います
if you've had a tropical holiday.
示したいと思います
海面水温の平面画像は
beautiful two-dimensional image
人工衛星で撮影されました
so it's got tremendous spatial resolution.
easy to understand.
実にわかりやすいものです
日射量が多いため温暖で
because there's more sunlight.
寒冷です
because there's less sunlight.
to build up on Antarctica
or even put your toes in the sea,
つま先を入れるだけでも
冷たくなるのが分かります
深海に広がる底層水は
that fill the abyss of the ocean
循環したものだからです
where the waters are dense.
20,000 years ago,
目にするであろう
of one of the major differences
if you went back that long.
海上まで広がっていました
and they extended out over the ocean.
今よりずっと低レベルでした
much lower than they are today.
全体的に3~5度低く
to five degrees colder overall,
更にずっと低かったと考えられます
in the polar regions.
are trying to understand,
昔の寒冷な気候から
cold climate condition
移り変わったのかです
that we enjoy today.
太陽放射量の緩やかな増加をもとに
cold conditions to warm conditions
安定的ではなかったことが分かります
from the slow increase in solar radiation.
because if you drill down into ice,
氷を下に掘り進めて行くと
氷山にもあります
and you can see this in the iceberg.
二酸化炭素濃度の測定が可能で
so we can measure CO2 --
低かったと知ることができます
was lower in the past --
極地の気温の情報も得られます
also tells us about temperature
2万年前から現代に来れば
from 20,000 years ago to the modern day,
has a lot to do with this.
確信しています
than is in the atmosphere.
熱を運ぶように作用し
across the equator,
これが基礎生産力を左右します
and it controls primary productivity.
what's going on down in the deep sea,
知るには
陸地から遠く離れた
coming from a seamount
in international waters
このような海底の映像を見たことある人は
to see this bit of the seafloor,
新種の生物を見ています
一心不乱に分類するだけです
and do some very intense taxonomy.
クモヒトデもいます
growing on these corals.
触手のようなものです
like tentacles coming out of corals.
炭酸カルシウムから成るサンゴが
of calcium carbonate
成長しています
massive undersea mountain,
化石化したサンゴです
those are fossilized corals,
これについてもう少し説明します
a little more about those
これについてもう少し説明します
to charter a research boat.
ジェームズ・クック号です
an ocean-class research vessel
a little more like this.
確認している場面です
that we don't lose precious samples.
私はひどい船酔いをしたりと
and I get terribly seasick,
大抵は楽しいです
but overall it is.
地図製作者になる必要がありました
a really good mapper to do this.
なかなかありません
coral abundance everywhere.
場所を見つける必要があります
the right places.
その上に重ねたのが
and overlaid was our cruise passage
独自に作成しましたが
of the seafloor in seven weeks,
of the seafloor.
海底は何の特徴もなく見えますが
look featureless on a big-scale map,
are as big as Everest.
エベレスト級の大きさです
十分ですが観察には不十分です
to deploy our equipment,
海底から約5メートルで
remotely-operated vehicles
1メートルの解像度の地図が得られます
that are one-meter resolution
1メートルの解像度の地図が得られます
大きなライトが見えます
of big lights on the top.
マニピュレーターアーム
manipulator arms,
多数の小箱などがあります
to put your samples.
of this particular cruise,
受けないように
the remotely operated vehicles
海綿動物がいます
it's a small sea slug, basically.
つまり小さなナマコです
実際は長時間かかるので
you is speeded up,
coming up was a big surprise.
皆さん驚くでしょう
一同が驚いたものです
and it took us all a bit surprised.
私たちが少しイライラしてきた頃
and we were all a bit trigger-happy,
くねりながら通ったのです
sea monster started rolling past.
群体ホヤと呼ばれています
or colonial tunicate, if you like.
ありませんでした
深海のサンゴです
deep sea corals.
of one in a moment.
触手が見えます
so you can see its tentacles there,
for about a hundred years.
恐らく100年は生きています
海から化学物質を取り込みます
chemicals from the ocean.
or the amount of chemicals,
異なります
it depends on the pH,
these chemicals get into the skeleton,
骨格に取り込まれるかが分かれば
collect fossil specimens,
再現できます
used to look like in the past.
真空装置でサンゴを収集し
that coral with a vacuum system,
言っておきます
carefully, I should add.
同僚のブレンダン・ロアークが
an image taken by my colleague,
撮影しました
meters below Hawaii.
of these corals and polish it up,
across this coral --
これをいくつかの分析にかけ
成功しました
that these are actual annual bands,
最盛期には届きません
us back to our last glacial maximum.
with my research team.
実に不人気です
there are swimming holothurians,
化石のある場所へ連れて行き
to these dead fossil areas
たっぷり時間をかけさせるのです
around on the seafloor.
bring them back, we sort them out.
持ち帰り 分類します
those chemical signals,
調査するのに役立ちます
in the ocean in the past.
注意深く磨いて
polished it very carefully
put it in a nuclear reactor,
評判の良くない元素ですが
事象が起きた年代を測定できます
about the rates and dates
突き止めたかったことです
when we're thinking about climate.
娘核種のトリウムを
thorium, in these corals,
分かります
how old the fossils are.
of the Southern Ocean
how we're using these corals
古代海洋の情報を―
説明していきましょう
ocean feedbacks.
of the surface water
この動画で
わかります
the Southern Ocean is.
集中的に混合している海域―
particularly the Drake Passage,
currents in the world
荒い海域の一つで
flowing from west to east.
激しく混合し
great big undersea mountains,
激しく混合し
二酸化炭素と熱を交換可能にします
with the atmosphere in and out.
南極海を介して呼吸しています
through the Southern Ocean.
across this Antarctic passage,
サンゴを収集し
驚くべき発見をしました
from my uranium dating:
移行している間に
移動していたのです
to the interglacial.
関連していると考えられます
to do with the food source
関連していると考えられます
気候についての見解を説明します
we've found about climate
サンゴの化石を集めました
We collected little fossil corals.
we've made in the corals,
was very rich in carbon,
知りました
layer sitting on top.
放出しないようにします
coming out of the ocean.
that are of an intermediate age,
中間年齢のサンゴにより
海水が混合したことが分かりました
partway through that climate transition.
放出されるようになります
out of the deep ocean.
closer to the modern day,
分析するか
移ったのだと分かります
where carbon can exchange in and out.
we can use fossil corals
with this last slide.
piece of footage that I showed you.
ご覧に入れた映像の抜粋です
to find things this beautiful.
サンゴの化石の真価を
to appreciate the fossil corals
飛行機で海を越えるか
to fly over the ocean
海底には―
sea mountains down there
ABOUT THE SPEAKER
Laura Robinson - Ocean scientistDr. Laura Robinson's scientific mission is to document and understand the processes that govern climate.
Why you should listen
Dr. Laura Robinson's research the processes that govern climate on time scales ranging from the modern day back through hundreds of thousands of years. To do this research, Robinson uses geochemical techniques, with an emphasis on radioactive elements including uranium series isotopes and radiocarbon. These elements are particularly valuable as they have a wide range of decay rates and geochemical properties and can be analyzed in geologic materials such as corals, marine sediments and seawater.
Through a combination of field work and lab work, Robinson has been tackling questions relating to: timing of Pleistocene climate change events; palaeoclimate reconstructions; deep-sea coral paleo-biogeography; impact of weathering on the ocean and climate; biomineralization; development of new geochemical proxies for past climate conditions; chemical tracers of ocean circulation.
Robinson describes the inspiration behind her work:
“When I finished my PhD, I moved to California to work with Professor Jess Adkins at Caltech on a project using deep-sea corals. Before that time, like many people, I did not know that corals lived in the deep ocean. The first thing I did was prepare for a research cruise to the North Atlantic. We took the research submarine 'Alvin' out to undersea mountains and were able to collect fossil corals from the seafloor. The start of my work in the Southern Ocean came from analysis of a single coral specimen from the Smithsonian Natural History Museum in Washington DC. They loaned us the sample, and we found that it was about 16,000 years old, just right for looking at the middle of the last global deglaciation. Being able to access and work on these specimens is a fantastic way of starting a science project. We published a paper on that sample, and then, together with a coral biologist, I wrote a proposal to fund specific expeditions to the Southern Ocean, and to the Equatorial Atlantic to gain a wider view of how the Atlantic Ocean behaved during major climate transitions.
I love the research as it combines field work, lab work and collaborations with all kinds of people including scientists, engineers as well as the ships' crews. In terms of scientists, I work with biologists, oceanographers, chemists, geologists, habitat specialists and a whole range of people who have technical expertise across these fields.”
Learn more about Robinson's current expidition in the Southern Ocean.
Laura Robinson | Speaker | TED.com