ABOUT THE SPEAKER
Laura Robinson - Ocean scientist
Dr. 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. 

More profile about the speaker
Laura Robinson | Speaker | TED.com
TEDxBrussels

Laura Robinson: The secrets I find on the mysterious ocean floor

Laura Robinson: Os segredos que eu encontro no misterioso fundo do mar

Filmed:
1,759,346 views

Centenas de metros abaixo da superfície do oceano, Laura Robinson examina as encostas íngremes de enormes montanhas submarinas. Ela está em busca de corais de centenas de anos para testá-los num reator nuclear e descobrir como o oceano muda com o tempo. Ao estudar a história da Terra, Robinson espera encontrar pistas do que pode acontecer no futuro.
- Ocean scientist
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.

Bem, eu sou oceanógrafa química.
00:12
Well, I'm an ocean chemist.
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00:14
I look at the chemistry
of the ocean today.
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Eu observo a química dos oceanos hoje.
Eu observo a química
dos oceanos no passado.
00:16
I look at the chemistry
of the ocean in the past.
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A maneira como observo o passado
00:19
The way I look back in the past
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é usando restos fossilizados
de corais de águas profundas.
00:21
is by using the fossilized remains
of deepwater corals.
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Podem ver uma imagem
de um desses corais aqui atrás.
00:24
You can see an image of one
of these corals behind me.
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Esse foi coletado próximo à Antártica,
milhares de metros debaixo do mar,
00:27
It was collected from close to Antarctica,
thousands of meters below the sea,
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00:31
so, very different
than the kinds of corals
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bem diferente dos tipos de corais
que vocês talvez tenham tido
a sorte de ver em uma viagem tropical.
00:33
you may have been lucky enough to see
if you've had a tropical holiday.
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E espero que essa palestra possa dar-lhes
uma visão em quatro dimensões do oceano.
00:37
So I'm hoping that this talk will give you
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00:39
a four-dimensional view of the ocean.
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00:41
Two dimensions, such as this
beautiful two-dimensional image
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Duas dimensões, como essa
bela imagem bidimensional
da temperatura na superfície marítima.
00:45
of the sea surface temperature.
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00:47
This was taken using satellite,
so it's got tremendous spatial resolution.
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Foi criada usando satélites,
portanto tem ótima resolução espacial.
00:51
The overall features are extremely
easy to understand.
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As características gerais
são simples de entender.
00:54
The equatorial regions are warm
because there's more sunlight.
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As zonas equatoriais são quentes
pois há mais luz solar.
00:58
The polar regions are cold
because there's less sunlight.
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As zonas polares são frias
pois há menos luz solar.
01:01
And that allows big icecaps
to build up on Antarctica
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E isso permite a formação
de grandes calotas de gelo na Antártica
01:04
and up in the Northern Hemisphere.
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e no Hemisfério Norte.
01:06
If you plunge deep into the sea,
or even put your toes in the sea,
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Se você for às profundezas do mar,
ou até mesmo molhar o pé no mar,
você sabe que fica mais frio
quanto mais fundo,
01:09
you know it gets colder as you go down,
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01:11
and that's mostly because the deep waters
that fill the abyss of the ocean
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e isso é porque as águas profundas
que preenchem os abismos do oceano
01:15
come from the cold polar regions
where the waters are dense.
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vêm das frias regiões polares
onde as águas são densas.
01:19
If we travel back in time
20,000 years ago,
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Se voltarmos 20 mil anos no tempo,
01:22
the earth looked very much different.
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a Terra era muito diferente.
01:24
And I've just given you a cartoon version
of one of the major differences
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E eu acabei de mostrar um desenho
de uma das maiores diferenças
01:28
you would have seen
if you went back that long.
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que teríamos visto
se voltássemos àquela época.
01:30
The icecaps were much bigger.
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As calotas eram muito maiores.
01:32
They covered lots of the continent,
and they extended out over the ocean.
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Cobriam uma grande parte do continente,
e se estendiam pelo oceano.
01:35
Sea level was 120 meters lower.
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O nível do mar estava 120 m mais baixo.
01:38
Carbon dioxide [levels] were very
much lower than they are today.
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Os níveis de dióxido de carbono
eram muito mais baixos que os atuais.
01:42
So the earth was probably about three
to five degrees colder overall,
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E a Terra estava entre
três e cinco graus mais fria em média,
01:45
and much, much colder
in the polar regions.
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e muitíssimo mais fria
nas regiões polares.
01:49
What I'm trying to understand,
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O que eu e outros colegas
estamos tentando entender,
01:51
and what other colleagues of mine
are trying to understand,
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é como passamos
daquela condição climática fria
01:54
is how we moved from that
cold climate condition
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para a condição climática quente
de que desfrutamos hoje.
01:56
to the warm climate condition
that we enjoy today.
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Sabemos por pesquisa de núcleo de gelo
01:59
We know from ice core research
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02:01
that the transition from these
cold conditions to warm conditions
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que a transição dessas condições
frias para condições quentes
02:04
wasn't smooth, as you might predict
from the slow increase in solar radiation.
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não foi gradual, como se esperaria
do lento aumento de radiação solar.
02:10
And we know this from ice cores,
because if you drill down into ice,
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E sabemos isso por núcleos de gelo,
pois quando perfuramos o gelo,
02:13
you find annual bands of ice,
and you can see this in the iceberg.
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encontramos faixas anuais de gelo,
e podemos vê-las no iceberg.
02:16
You can see those blue-white layers.
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Vemos aquelas camadas azuis e brancas.
02:18
Gases are trapped in the ice cores,
so we can measure CO2 --
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Os gases ficam presos nos núcleos de gelo,
e assim conseguimos medir o CO2;
02:22
that's why we know CO2
was lower in the past --
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é assim que sabemos que havia
menos CO2 no passado;
02:24
and the chemistry of the ice
also tells us about temperature
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e a química do gelo também
nos informa sobre a temperatura
02:27
in the polar regions.
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nas regiões polares.
02:29
And if you move in time
from 20,000 years ago to the modern day,
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E se avançarmos no tempo,
de 20 mil anos atrás aos dias atuais,
02:32
you see that temperature increased.
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vemos que a temperatura subiu.
02:34
It didn't increase smoothly.
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Não subiu aos poucos.
02:36
Sometimes it increased very rapidly,
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Às vezes subiu rapidamente,
02:38
then there was a plateau,
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e ficava estável,
02:39
then it increased rapidly.
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e aumentava rapidamente.
02:40
It was different in the two polar regions,
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Foi diferente nas duas regiões polares,
e CO2 também aumentou aos saltos.
02:42
and CO2 also increased in jumps.
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02:46
So we're pretty sure the ocean
has a lot to do with this.
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E temos bastante certeza que o oceano
tem muito a ver com isso.
02:49
The ocean stores huge amounts of carbon,
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O oceano armazena enormes
quantidades de carbono,
02:52
about 60 times more
than is in the atmosphere.
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cerca de 60 vezes mais
do que o que há na atmosfera.
02:54
It also acts to transport heat
across the equator,
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Também serve para transportar
o calor através do equador,
02:58
and the ocean is full of nutrients
and it controls primary productivity.
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E o oceano é cheio de nutrientes
e controla a produtividade primária.
03:02
So if we want to find out
what's going on down in the deep sea,
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Portanto, se quisermos entender
o que acontece no fundo do mar,
03:05
we really need to get down there,
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realmente temos que ir até lá,
03:06
see what's there
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ver o que há lá
e começar a explorar.
03:07
and start to explore.
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03:09
This is some spectacular footage
coming from a seamount
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Eis um vídeo espetacular
de uma montanha submarina
a um quilômetro de profundidade
em águas internacionais
03:12
about a kilometer deep
in international waters
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03:14
in the equatorial Atlantic, far from land.
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no Atlântico equatorial,
longe do continente.
Vocês são alguns dos primeiros
a ver esse pedaço do fundo do mar,
03:17
You're amongst the first people
to see this bit of the seafloor,
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junto com minha equipe de pesquisa.
03:20
along with my research team.
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Aí provavelmente há novas espécies.
03:23
You're probably seeing new species.
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Nós não sabemos.
03:25
We don't know.
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03:26
You'd have to collect the samples
and do some very intense taxonomy.
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Teríamos que coletar as amostras
e realizar uma taxonomia bem intensiva.
03:29
You can see beautiful bubblegum corals.
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Dá para var belos corais coloridos.
03:31
There are brittle stars
growing on these corals.
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Há estrelas quebradiças
crescendo nesses corais.
03:34
Those are things that look
like tentacles coming out of corals.
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São as coisas que parecem
tentáculos saindo dos corais.
Há corais feitos de diferentes
formas de carbonato de cálcio
03:37
There are corals made of different forms
of calcium carbonate
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crescendo no basalto
dessa enorme montanha submarina,
03:40
growing off the basalt of this
massive undersea mountain,
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03:43
and the dark sort of stuff,
those are fossilized corals,
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e o material meio escuro,
esses são os corais fossilizados,
03:46
and we're going to talk
a little more about those
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e vamos falar um pouco mais sobre eles
à medida que voltamos no tempo.
03:49
as we travel back in time.
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03:51
To do that, we need
to charter a research boat.
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Para isso, precisamos fretar
um barco de pesquisa.
03:53
This is the James Cook,
an ocean-class research vessel
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Esse é o James Cook, uma embarcação
de pesquisa oceânica
03:56
moored up in Tenerife.
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ancorado em Tenerife.
03:57
Looks beautiful, right?
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É bonito, não é?
Ótimo, se você não for
um grande marinheiro.
03:59
Great, if you're not a great mariner.
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04:01
Sometimes it looks
a little more like this.
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Às vezes ele fica mais assim.
04:04
This is us trying to make sure
that we don't lose precious samples.
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Aqui estamos nós garantindo
a preservação de amostras preciosas.
04:07
Everyone's scurrying around,
and I get terribly seasick,
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Todos correndo,
e eu fico com um enjoo terrível,
04:10
so it's not always a lot of fun,
but overall it is.
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portanto não é sempre divertido,
mas em geral é.
04:13
So we've got to become
a really good mapper to do this.
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E nós temos que ser muito bons
mapeadores para fazer isso.
04:15
You don't see that kind of spectacular
coral abundance everywhere.
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Não se vê essa espetacular abundância
de corais em todo lugar.
04:19
It is global and it is deep,
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É global e é profunda,
mas temos que encontrar
realmente os melhores lugares.
04:22
but we need to really find
the right places.
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Acabamos de ver um mapa-múndi
e sobreposta estava nossa passagem
04:25
We just saw a global map,
and overlaid was our cruise passage
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do ano passado.
04:28
from last year.
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Foi um cruzeiro de sete semanas,
04:29
This was a seven-week cruise,
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e aqui somos nós, tendo criado
nossos próprios mapas
04:31
and this is us, having made our own maps
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04:33
of about 75,000 square kilometers
of the seafloor in seven weeks,
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de cerca de 75 mil km²
do fundo do mar em sete semanas,
mas isso é só uma pequena
fração do fundo do mar.
04:37
but that's only a tiny fraction
of the seafloor.
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Estamos viajando do oeste para o leste,
04:40
We're traveling from west to east,
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04:41
over part of the ocean that would
look featureless on a big-scale map,
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sobre uma parte que seria inexpressiva
em um mapa de grande escala,
mas, na verdade, algumas dessas montanhas
são tão altas quanto o Everest.
04:45
but actually some of these mountains
are as big as Everest.
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04:48
So with the maps that we make on board,
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E com os mapas que criamos a bordo,
04:50
we get about 100-meter resolution,
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temos uma resolução
de cerca de 100 metros,
04:52
enough to pick out areas
to deploy our equipment,
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suficiente para detectar áreas
para lançar nosso equipamento,
04:55
but not enough to see very much.
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mas não o suficiente
para ver muita coisa.
04:57
To do that, we need to fly
remotely-operated vehicles
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Para isso, precisamos pilotar
veículos de controle remoto
05:00
about five meters off the seafloor.
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a cerca de cinco metros
acima do fundo do mar.
05:02
And if we do that, we can get maps
that are one-meter resolution
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E, se fizermos isso, conseguimos mapas
com resolução de um metro
05:05
down thousands of meters.
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a milhares de metros de profundidade.
05:07
Here is a remotely-operated vehicle,
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Este é um veículo de controle
remoto para pesquisa.
05:09
a research-grade vehicle.
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Dá para ver uma série
de grandes luzes em cima.
05:12
You can see an array
of big lights on the top.
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05:14
There are high-definition cameras,
manipulator arms,
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Há câmeras de alta definição,
braços para manipulação,
05:17
and lots of little boxes and things
to put your samples.
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e várias caixas e coisinhas
para depositar as amostras.
05:21
Here we are on our first dive
of this particular cruise,
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Aqui estamos no nosso primeiro
mergulho desse cruzeiro,
imergindo no oceano.
05:24
plunging down into the ocean.
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Vamos bem rápido para garantir
que os veículos de controle remoto
05:26
We go pretty fast to make sure
the remotely operated vehicles
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não sejam afetados por outros navios.
05:29
are not affected by any other ships.
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05:31
And we go down,
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E descemos,
05:32
and these are the kinds of things you see.
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e esse é o tipo de coisa que se vê.
05:34
These are deep sea sponges, meter scale.
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Essas são esponjas marinhas, à escala.
05:38
This is a swimming holothurian --
it's a small sea slug, basically.
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Esse é uma holotúria nadando:
basicamente uma lesma marinha.
Aqui está desacelerado.
05:43
This is slowed down.
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05:44
Most of the footage I'm showing
you is speeded up,
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A maioria dos vídeos
que estou mostrando está acelerada,
05:46
because all of this takes a lot of time.
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porque isso tudo demora muito.
05:49
This is a beautiful holothurian as well.
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Aqui também uma bela holotúria.
05:52
And this animal you're going to see
coming up was a big surprise.
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E esse animal que vai aparecer subindo
foi uma grande surpresa.
Eu nunca vi nada como isso,
e nos deixou todos surpresos.
05:55
I've never seen anything like this
and it took us all a bit surprised.
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Depois de umas 15 horas de trabalho,
estávamos todos um pouco irritados,
05:59
This was after about 15 hours of work
and we were all a bit trigger-happy,
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e de repente esse monstro marinho
gigante passou nadando.
06:03
and suddenly this giant
sea monster started rolling past.
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Chama-se pirossomo,
ou tunicata colonial, se preferirem.
06:05
It's called a pyrosome
or colonial tunicate, if you like.
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06:08
This wasn't what we were looking for.
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Não era o que estávamos procurando.
06:10
We were looking for corals,
deep sea corals.
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estávamos procurando por
corais de águas profundas.
06:14
You're going to see a picture
of one in a moment.
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Logo vamos ver a imagem de um.
06:16
It's small, about five centimeters high.
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É pequeno, cerca de cinco
centímetros de altura.
06:19
It's made of calcium carbonate,
so you can see its tentacles there,
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É feito de carbonate de cálcio,
e dá para ver seus tentáculos.
06:22
moving in the ocean currents.
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movendo-se com as correntes do oceano.
06:25
An organism like this probably lives
for about a hundred years.
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Um organismo desses provavelmente
vive por cerca de cem anos.
06:28
And as it grows, it takes in
chemicals from the ocean.
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E, enquanto cresce, absorve
substâncias do oceano.
E as substâncias,
ou a quantidade de substâncias,
06:31
And the chemicals,
or the amount of chemicals,
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depende da temperatura;
depende do pH e dos nutrientes.
06:34
depends on the temperature;
it depends on the pH,
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06:36
it depends on the nutrients.
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E se conseguirmos entender como
esses nutrientes entram no esqueleto,
06:38
And if we can understand how
these chemicals get into the skeleton,
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06:41
we can then go back,
collect fossil specimens,
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podemos voltar,
coletar espécimes fósseis,
06:44
and reconstruct what the ocean
used to look like in the past.
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e reconstruir o oceano
como ele era no passado.
06:47
And here you can see us collecting
that coral with a vacuum system,
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E aqui estamos coletando um coral
com um sistema a vácuo,
e colocando-o num frasco de amostra.
06:50
and we put it into a sampling container.
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Devo dizer que o fazemos
com bastante cuidado.
06:53
We can do this very
carefully, I should add.
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Alguns desses organismos
chegam a viver mais tempo.
06:55
Some of these organisms live even longer.
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06:57
This is a black coral called Leiopathes,
an image taken by my colleague,
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Este é um coral negro, o "Leiopathes",
numa foto do meu colega
07:01
Brendan Roark, about 500
meters below Hawaii.
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Brendan Roark, tirada a cerca de 500 m
de profundidade no Havaí.
Quatro mil anos é muito tempo.
07:04
Four thousand years is a long time.
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Coletamos e polimos um ramo
de um desses corais.
07:06
If you take a branch from one
of these corals and polish it up,
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Este tem cerca de 100 micrômetros
de espessura,
07:10
this is about 100 microns across.
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e Brendan o analisou,
07:12
And Brendan took some analyses
across this coral --
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07:15
you can see the marks --
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dá para ver as marcas,
07:17
and he's been able to show
that these are actual annual bands,
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que ele mostrou serem anéis anuais.
Portanto, mesmo a 500 m de profundidade,
07:20
so even at 500 meters deep in the ocean,
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07:22
corals can record seasonal changes,
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os corais conseguem registrar
as mudanças sazonais,
07:24
which is pretty spectacular.
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o que é fantástico.
07:26
But 4,000 years is not enough to get
us back to our last glacial maximum.
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Mas 4 mil anos não é suficiente
para nos levar à última máxima glacial.
Então, o que fizemos?
07:30
So what do we do?
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07:31
We go in for these fossil specimens.
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Fomos atrás dessas espécies fósseis.
07:34
This is what makes me really unpopular
with my research team.
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Isso é o que me torna tão impopular
com meu grupo de pesquisa:
continuando,
07:37
So going along,
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há tubarões gigantes por toda a parte,
07:38
there's giant sharks everywhere,
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07:39
there are pyrosomes,
there are swimming holothurians,
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há piossomos, há holotúrias nadadoras,
07:42
there's giant sponges,
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esponjas gigantes,
mas faço todo mundo mergulhar
em áreas de fósseis mortos
07:43
but I make everyone go down
to these dead fossil areas
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07:46
and spend ages kind of shoveling
around on the seafloor.
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e passar horas cavucando o fundo do mar.
Aí, coletamos os corais, trazemos
para cima e os separamos.
07:49
And we pick up all these corals,
bring them back, we sort them out.
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Cada um é de uma era diferente,
07:53
But each one of these is a different age,
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mas, se conseguirmos descobrir sua idade
07:55
and if we can find out how old they are
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e medir esses sinais químicos,
07:57
and then we can measure
those chemical signals,
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isso vai nos ajudar a descobrir
08:00
this helps us to find out
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08:01
what's been going on
in the ocean in the past.
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o que acontecia no oceano no passado.
08:04
So on the left-hand image here,
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Assim, na imagem à esquerda,
peguei uma lâmina de um coral
e poli cuidadosamente,
08:06
I've taken a slice through a coral,
polished it very carefully
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e tirei uma foto pelo microscópio.
08:09
and taken an optical image.
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08:11
On the right-hand side,
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À direita, pegamos o mesmo coral,
colocamos num reator nuclear,
08:12
we've taken that same piece of coral,
put it in a nuclear reactor,
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induzimos uma fissão
08:15
induced fission,
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08:16
and every time there's some decay,
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e sempre que houve uma deterioração,
como mostram as marcas aqui no coral,
08:18
you can see that marked out in the coral,
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08:20
so we can see the uranium distribution.
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pode-se ver a distribuição do urânio.
Por que fazemos isso?
08:22
Why are we doing this?
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08:23
Uranium is a very poorly regarded element,
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O urânio é um elemento com má fama,
mas eu o adoro.
08:25
but I love it.
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08:27
The decay helps us find out
about the rates and dates
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A deterioração nos ajuda
a desvendar as taxas e as datas
do que está acontecendo no oceano.
08:30
of what's going on in the ocean.
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E, como falei no início,
08:31
And if you remember from the beginning,
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é aonde queremos chegar
quando pensamos em clima.
08:33
that's what we want to get at
when we're thinking about climate.
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Assim, usamos um laser
para analisar o urânio
08:36
So we use a laser to analyze uranium
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1751
08:38
and one of its daughter products,
thorium, in these corals,
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e um de seus elementos filhos,
o tório, nesses corais,
e isso nos dá a idade
exata desses fósseis.
08:41
and that tells us exactly
how old the fossils are.
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08:44
This beautiful animation
of the Southern Ocean
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Esta linda animação do Oceano Antártico
vai ser usada agora para ilustrar
como usamos esses corais
08:46
I'm just going to use illustrate
how we're using these corals
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514958
3135
08:50
to get at some of the ancient
ocean feedbacks.
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4071
para conseguir as respostas
sobre o passado do oceano.
08:54
You can see the density
of the surface water
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2426
Dá para ver a densidade
da superfície da água
08:56
in this animation by Ryan Abernathey.
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nesta animação de Ryan Abernathey.
08:59
It's just one year of data,
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2037
Trata-se de um ano de dados apenas,
09:01
but you can see how dynamic
the Southern Ocean is.
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mas dá para ver o quanto
o Oceano Antártico é dinâmico.
A intensa mistura, particularmente
na passagem de Drake,
09:04
The intense mixing,
particularly the Drake Passage,
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09:07
which is shown by the box,
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mostrada aqui dentro do quadrado,
é realmente um das correntes
mais fortes do mundo
09:10
is really one of the strongest
currents in the world
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que passa ali, fluindo
do oeste para o leste.
09:13
coming through here,
flowing from west to east.
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É uma mistura muito turbulenta,
09:15
It's very turbulently mixed,
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09:16
because it's moving over those
great big undersea mountains,
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pois está se movendo sobre
grandes montanhas submersas,
e isso permite a troca de CO2
e calor com a atmosfera.
09:19
and this allows CO2 and heat to exchange
with the atmosphere in and out.
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4481
09:24
And essentially, the oceans are breathing
through the Southern Ocean.
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Basicamente, os oceanos respiram
através do Oceano Antártico.
09:28
We've collected corals from back and forth
across this Antarctic passage,
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Coletamos corais de diversos
locais nessa passagem Antártica,
e descobrimos uma coisa surpreendente
na minha datação do urânio:
09:34
and we've found quite a surprising thing
from my uranium dating:
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os corais migraram do sul para o norte
09:37
the corals migrated from south to north
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09:39
during this transition from the glacial
to the interglacial.
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durante a transição do glacial
para o interglacial.
Não sabemos bem a razão,
09:43
We don't really know why,
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1207
mas achamos que tenha a ver
com a fonte alimentar
09:44
but we think it's something
to do with the food source
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2549
e talvez com o oxigênio na água.
09:46
and maybe the oxygen in the water.
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Bem, aqui estamos,
09:49
So here we are.
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e vou ilustrar o que acho
que descobrimos sobre o clima
09:50
I'm going to illustrate what I think
we've found about climate
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com esses corais do Oceano Antártico.
09:53
from those corals in the Southern Ocean.
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1960
Escalamos montanhas submarinas
coletando pequenos corais fósseis.
09:55
We went up and down sea mountains.
We collected little fossil corals.
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Eis minha ilustração disso.
09:59
This is my illustration of that.
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Achamos que, na era glacial,
10:00
We think back in the glacial,
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com base nas análises dos corais,
10:02
from the analysis
we've made in the corals,
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2023
o fundo do Oceano Antártico
era rico em carbono,
10:04
that the deep part of the Southern Ocean
was very rich in carbon,
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3086
e havia uma camada
de baixa densidade no topo.
10:07
and there was a low-density
layer sitting on top.
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2689
10:10
That stops carbon dioxide
coming out of the ocean.
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2793
Isso impede a saída
do dióxido de carbono do oceano.
10:13
We then found corals
that are of an intermediate age,
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2592
Então, encontramos corais
de uma era intermediária,
10:16
and they show us that the ocean mixed
partway through that climate transition.
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evidenciando uma mistura parcial
durante aquela mudança climática.
Isso permite ao carbono
deixar o fundo do oceano.
10:20
That allows carbon to come
out of the deep ocean.
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2467
10:24
And then if we analyze corals
closer to the modern day,
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Depois, analisamos os corais
com idade mais recente,
e, de fato, se descermos lá hoje
10:27
or indeed if we go down there today anyway
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2254
10:29
and measure the chemistry of the corals,
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e medirmos a química dos corais,
10:31
we see that we move to a position
where carbon can exchange in and out.
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veremos que passamos para uma posição
em que o carbono pôde fazer trocas.
10:35
So this is the way
we can use fossil corals
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2074
Então, é assim que usamos corais fósseis
10:37
to help us learn about the environment.
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1942
para tentar entender o meio ambiente.
10:41
So I want to leave you
with this last slide.
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Bem, quero terminar com este último slide.
10:43
It's just a still taken out of that first
piece of footage that I showed you.
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É apenas um instantâneo tirado daquela
primeira parte do filme que lhes mostrei.
Este é um jardim de corais espetacular.
10:47
This is a spectacular coral garden.
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2112
Nem esperávamos encontrar
algo assim tão bonito.
10:50
We didn't even expect
to find things this beautiful.
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2558
Fica a milhares de metros de profundidade.
10:52
It's thousands of meters deep.
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1884
10:54
There are new species.
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1374
Existem espécies novas.
10:56
It's just a beautiful place.
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1899
É um lugar simplesmente lindo.
Existem fósseis no meio,
10:58
There are fossils in amongst,
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10:59
and now I've trained you
to appreciate the fossil corals
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2691
e agora eu os ensinei
a apreciar os corais fósseis
11:02
that are down there.
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que estão lá embaixo.
Assim, da próxima vez que tiverem
a sorte de sobrevoar o oceano
11:03
So next time you're lucky enough
to fly over the ocean
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11:06
or sail over the ocean,
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ou velejar pelo oceano,
11:08
just think -- there are massive
sea mountains down there
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pensem: há enormes montanhas lá embaixo
11:10
that nobody's ever seen before,
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1867
nunca antes vistas e lindos corais.
11:12
and there are beautiful corals.
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Obrigada.
11:14
Thank you.
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(Aplausos)
11:15
(Applause)
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Translated by Gustavo Rocha
Reviewed by Raissa Mendes

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ABOUT THE SPEAKER
Laura Robinson - Ocean scientist
Dr. 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. 

More profile about the speaker
Laura Robinson | Speaker | TED.com