martes, 3 de abril de 2012

From the surface for a deeper understanding


Supongo que podría parecer que lo que hice en mi Tesis y lo que hago ahora son cosas que distan bastante una de la otra. Bueno, entiendo que para alguien que no trabaje en algo parecido lo que digo puede parecer una tontería, al fin y al cabo se trata de oceanografía ¿no? Vale, en eso os doy la razón. Aun así, (1) el estudio de la interacción océano-atmósfera y la capa de mezcla en latitudes medias y (2) las masas de aguas profundas del Ártico no son cosas a priori próximas. Por si alguien anda perdido, en los links de abajo os comentaba más sobre ambas cosas: (1) mi trabajo durante la Tesis y (2) mi trabajo actualmente.

I suppose it might seem that what I did in my PhD and what I do now are things quite different from each other. Well, I understand that for someone who doesn’t work in something similar what I say may seem silly; at the end, it’s oceanography, isn’t it? Okay, I agree with you on that point. Still, (1) the study of the ocean-atmosphere interaction and the mixed layer at mid-latitudes and (2) the deep water masses of the Arctic Ocean are not a priori close things. Just in case someone is lost, in the links below you have more information about (1) my PhD work and (2) my work nowadays

Sin embargo, últimamente se han publicado algunos trabajos que me han hecho pensar en lo que relaciona  ambas cosas. Resulta que recientes medidas indican que mientras el calor recibido en la atmósfera ha aumentado no lo ha hecho igualmente el calor almacenado en las capas superficiales del océano (primeros 700 metros) (1,2).  Esto plantea la pregunta de ...¿donde está el resto de ese calor puesto que las medidas no indican que haya escapado de nuevo al espacio? Como sabéis, el océano es el gran almacén del calor del Sol que recibe la Tierra. Así que todo apunta a que ese calor ha pasado 'directamente' a las capas profundas del océano. La cuestión es CÓMO. 

Anteriormente, hasta el inicio aproximadamente del nuevo siglo, la mayor parte del aumento de temperatura generalizado que hoy observamos se estaba viendo absorbido por las capas superficiales del océano. La situación actual implica, por una lado, que el exceso de calor en la atmósfera debe pasar a través de las capas superficiales y la capa de mezcla hacia el océano profundo y, por otro, que debe hacerlo de manera más efectiva a como lo hacía antes (antes la mayoría se quedaba en las capas superficiales y ahora no). Esto me lleva al objeto de estudio de mi Tesis, la interacción océano-atmósfera y los procesos en la capa de mezcla.

However, some recently published studies have made me think about how both topics relate. It turns out that recent measurements indicate that while the heat received in the atmosphere has increased, the heat storage in the upper ocean (first 700 meters) has growth at a lower rate (1,2). As you probably already know, the Ocean is the main heat reservoir of the Earth’s climate system. This makes arise the question about where's the remaining heat received in the atmosphere taking into account that measurements don’t indicate it has escaped back into space. It seems that the heat has been 'directly injected’ to the deep ocean. The question now is HOW.

Previously, until the beginning of the new century approximately, the surface layers of the Ocean absorbed most of the generalized temperature increase that we observed. The different situation nowadays implies, on the one hand, that the excess of heat in the atmosphere must pass through the surface and mixed layer to the deep ocean; and, on the other, that the process transferring the heat from the atmosphere to the deep ocean must do it more efficiently now than before (Remember that before most of the heat in the atmosphere was accumulated in the surface layers but now it's supposed to be in the deep ocean). This brings me to the subject of my PhD, the ocean-atmosphere interaction and the processes in the mixed layer.

Después ese calor 'se debe estar almacenando' en el océano profundo. Eso es lo que estudio ahora. En concreto, las masas de agua profundas del Ártico las cuales podrían jugar un papel importante en ese calor perdido, puesto que sus cambios apenas han sido estudiados hasta ahora. De hecho, muy pocos datos del Ártico se han incluido normalmente en los estudios relacionados con el almacenamiento de calor en el océano (3).

Later, that heat must be stored in the deep ocean. That's what I study now, specifically, the deep water masses of the Arctic Ocean, which could play an important role on that missing heat, since their changes have hardly been studied so far. In fact, few Arctic data have been included in studies dealing with the World Ocean heat content (3).

En fin, un montón de cosas por estudiar y a las que, si existe, me encantaría encontrar el nexo de unión.

Anyway, a lot of things to study and to which, if any, I would love to find the link.



No tiene nada que ver pero no quería dejar el post sin una bonita imagen, y ya os he hablado de esta página de la NASA (http://visibleearth.nasa.gov). No tiene despercidio.


(1) Tracking Earth’s Energy Kevin E. Trenberth, et al. Science 328, 316 (2010) DOI: 10.1126/science.1187272
(2) Katsman, C. A., and G. J. van Oldenborgh (2011), Tracing the upper ocean’s “missing heat,” Geophys. Res. Lett., 38, L14610, doi:10.1029/2011GL048417.
(3) Levitus, S.et al (2009), Global ocean heat content 1955–2008 in light of recently revealed instrumentation problems, Geophys. Res. Lett., 36, L07608, doi:10.1029/2008GL037155.

5 comentarios:

  1. Hi
    I believe you mention your thesis. Can this thesis be found somewhere on the net? (I do expect it is not written in Spanish)

    beste groeten

    E.

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    Respuestas
    1. Hi,

      Good to hear from you again. What I explain in this post is the relation of the work during my PhD and my work now in the Arctic Ocean. I will try to write it in English.

      About the work that I did in my PhD, you can read a little bit in the post http://fromtheblueside.blogspot.de/2012/03/about-my-work-i.html. It is written in English. I don't think that the complete document of my Thesis is available, but if you tell me what kind of information you are looking for I could send you some of the papers that I have published based on the work during my PhD.

      ßeste Grüße,

      Raquel

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  2. Hi

    by now I have googled and found out that your thesis seems to have been about the Biskaya. Mixing. "capa de mezcla" means Mixed Layer, right?

    Of course you are right, I should explain my interest! I´m simply a reader attracted to following the arctic through Neven´s ASI blog. There´s a community of more or less normal folks there watching the arctic trying to make sense of what´s going on. I´m not even part of "them", I´m just a reader (and a native of the Elbe-Weser-Dreieck, not far from Bremerhaven). I have been more than impressed with the enormous amount of data that is apparently available if one knows where to look on the web, but quite often (as a plain citizen) one just doesnt understand what one looks at. So you are a professional in these things, could one ask you questions about them?

    people on blogs say many things, and often enough the knowledge is not there to make the distinction between realistic descriptions and fables (like: could Greenland, the ice shield, slip into the sea within a span of a few years? I believe its a fable, but I couldnt argue the point). So when you say that you study the energy exchange between upper arctic ocean water layers and atmosphere (?) then that is exactly what people wonder about ...
    Could you now and again explain things?

    to make it totally concrete: right now it looks like the Beaufort Sea doesnt want to freeze over. How can that be? Should not the uppermost ocean lose all its warmth to the cold air and freeze? Does it tell us anything that that doesnt happen there? Is the whole arctic soon going to be seasonal? If it is, will all the sweet water (Suesswasser) that now lies under the ice and protect it, mix into the big ocean and vanish, and will the whole arctic become like the North Atlantic? If that happens what does that mean for our weather? What signs should one watch up North to have an expectation of what is to come? Why are all the climate models so wrong? (The latter one is a big fight: some people say that one cannot trust science because science cant predict the ice loss speed, and therefore we have to expect catastrophe. I refuse to give up science but I cant argue that point either).

    OK, I hope that wasnt too much. just to explain my motivation. I am not looking for a specific paper - rather for insight ...

    (also it is fun to read a wholly unknown language and guess at what it means)

    groeten

    E.

    I will have quite a while to do with working through the various posts here!

    Also, I am not a robot!

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    1. Hi,

      Sorry for the delay in my answer. From my knowledge, but it doesn't include the Greenland ice sheet or the Beaufort gyre specifically, I would say that the answer to your questions is no in both cases.

      I don't know the melting rates of the Greenland ice sheet, but to make it disappear in few years (10 years) they should be HUGE! I don't know neither how many years you have read this process can take. If we talk about 30 years, I would say it is reasonable, again without knowledge of the melting rates and volumes of the Greenland ice sheet. I will check these numbers for you, and I will give an answer based on this data and with a short explanation of how it can happen.

      Regarding the absence of freezing in the Beaufort Gyre, I find really strange what you mention. For the Eurasian basin of the Arctic, this is not what you can expect. I mean, we have reaaaaally large melt during the summer, but the air temperatures during the winter continue being really low. It makes the sea surface to loss heat until its temperature decreases until the freezing point, and then ice formation take place. I can not imagine how in the Beaufort gyre during the winter the temperatures in the Arctic could be above 0°C, and so avoid the ice formation. If you give me the link where you read that, I can read also and try to explain you what they say.

      It's really nice to see that people like you is more, and more interested in these questions. I was considering for a while to make a section where people can suggest directly a topic through some questions they want to know more about. Now, I'm sure I will do very soon. Many, many thanks.

      ßeste Grüße,

      Raquel

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  3. Hi

    that would be a great thing: a section where people can indicate what they have questions about. "Ask an oceanographer" section !

    have to run to work, but I want to say that this is a good & interesting place & I´ll continue to watch it for new things, even though new things in science come at a somewhat slower pace than elsewhere :)

    groeten

    E.



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Muchas gracias por tu comentario.
Many thanks for your comment.

Raquel