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Atlantic on my mind

In recent times there has been a lot of talk about ocean circulation in relation to a changing climate, specifically the AMOC, that is, the Atlantic Meridional Overturning Circulation and its best-known part flowing on the surface, the Gulf Stream.

This is a topic that comes back to the fore every now and then, whether it is research (good and right) or media speculation (much less interesting), as in the case of the blockbuster The Day After Tomorrow, of which, among other things, on these pages you will find several er… reviews :-).

For this Sunday now almost over, I therefore recommend a few readings on the subject, to be done, however, taking into account a couple of non-trivial elements of knowledge that are hardly remembered:

  1. The thermoaline circulation, that is, the complex system of surface and depth ocean currents, depends, as is clear from the name, on both temperature and salinity, but is set in motion in the same way as atmospheric circulation by the astronomical motions of the planet that condition the redistribution of heat on Earth. Among them, the rotation around the axis and the consequent coriolis force. Changes in temperature and salinity therefore certainly affect these motions, but to stop them it would also be necessary to stop the planet.
  2. The above does not prevent these motions from changing, indeed their change is the basis of climate evolutions, precisely as a direct effect of astronomical inputs. Specifically, a possible slowdown in the Gulf Stream, due to changes in salinity induced by the spillage of fresh water into the North Atlantic from the melting of the earth’s glacial masses (non-marine!), would lead to changes in atmospheric circulation that would favor a cooling of a substantial part of the land of the northern hemisphere. This is a mechanism that is thought to be at the origin of millennial trends that then lead to the incipit of glacial phases.

Against this background, here are the readings for this Sunday.

First, a recently published paper in which, using proximity data and model simulations, the authors come to the conclusion that AMOC would now be at its millennial lows. The acceleration of the slowdown (excuse the pun), however, would have come in the last decades:

Current Atlantic Meridional Overturning Circulation weakest in last millennium – Nature Geoscience

The study is explained in an exhaustive TD on Twitter:

Then another paper, also very recent, which says instead that despite the fact that decelerations have been detected, the trend of the last thirty years of AMOC would be not significant, therefore quite in contrast to what was claimed in the other study. The periods under review are significantly different, but the last one coincides:

A 30-year reconstruction of the Atlantic south overturning circulation shows no decline – EGU Ocean Science

And then another very recent study that looked at the freshwater flow of the Beaufort Gyre (BG), the largest low-salinity water reservoir in the North Atlantic as well as part of AMOC. According to this study, low salinity water has increased significantly in recent decades:

Labrador Sea freshening linked to Beaufort Gyre freshwater release – Nature Communication

Before closing and wishing you a good read, a couple more considerations:

  1. The ability to observe these phenomena has increased enormously in recent times, so connecting what we “see” now with what has happened in the past and that we know thanks to proxi data is extremely difficult and not free from wide margins of uncertainty.
  2. The presence of dynamics that would in fact lead to cooling is a confirmation of the existence of mechanisms that prevent the so-called runaway greenhouse effect, that is, a tendency to uncontrolled heating triggered to reach points of no return that have no scientific reason to exist but instead go very fashionable.


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Cheerfulness, the end of the world recedes

It’s time to party. At this time, in the French armored capital, the great and the good are starting to pose for the flashes and then discuss with the firm intention to agree on the following agenda:

  • Defeat terrorism
  • Permanently delete world hunger
  • Put an end to any kind of armed conflict
  • Turn all the weapons factories in chocolate factories
  • Delete all kinds of social and economic inequality

Would you like to huh? And yet nothing, the gathering of powerful will take place, but none of these arguments will be subject of negotiation. They will talk about saving the world from being warmer, that is, according to the unique facts hitherto attributed to increase in average global temperature as a result of an increased concentration of carbon dioxide in the atmosphere, from being greener. It will be a case, for heaven’s sake, but while we’re all here waiting that the gloomy predictions of a climate ‘disrupted’ by reason of heating comes true, the only thing actually measured is the benefit that the plants around the world, be it forests or crops, are benefiting from increased availability of the substance they eat, precisely CO2 and favorable climatic conditions like those, up to a thousand years ago, allowed and facilitated the development of our civilization.

Something that, of course, the powerful of the earth they are going to reverse. Or not? This is also to be seen. So it would be if at the end in Paris, they really came to a legally binding agreement on reducing emissions, because – is pretty clear to to everyone – the decarbonisation as you would like is not economically viable. None of the available energy resource guarantees the amount of energy equal to current demand, not even to speak of the future, at costs comparable to those of fossil fuels. So we will use less energy and, given that welfare is in the availability of large amounts of cheap energy, we should feel worse. We do it for the world’s poor? No, because despite some high official of the IPCC claims that summits like the one in Paris are not on the climate but on redistribution of global income (Oppenheimer, co-chair of the IPCC, nomen omen), what we would call the most are the poor, for whom the cheap energy today need to grow up and stop being poor.

So we are going to have an agreement, but not in the form in which it would make sense, if not granted you could decide around a table what the weather will be in 10, 50, 100 years or more. But, no one will come away defeated in its picture, the only thing that politically really matters, and the signatures will shine on a document where all will commit, voluntarily, to do what they promised to do and that it’s already known that is not going to help.

This, in summary and with some additions, the idea that Matt Ridley and Benny Peiser put just yesterday in the Wall Street Journal.

Your Complete Guide To The Paris Climate Summit

Attention, to read it in full you need a subscription, but you find it almost in its entirety on the website of the GWPF.

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In the land of windmills electric cars run on coal

electriccarsThe fact that in the Netherlands there were the windmills and in our country there were watermills is probably no accident. Constantly exposed to the westerlies, the intense western flow that blow in from the Atlantic towards Europe, the Netherlands is a country with a strong wind power potential. Proof of this is the fact that production both inland and off-shore by the end of 2014 reached a production of just under 3GW, just over one-third of the Italian production, within a much smaller territory.

A viable territory in just a few hours in each direction, is ideal for the use of electric cars, whose low environmental impact per vehicle, suffers, with current technology available, with poor range. In fact, the Netherlands is the second largest country in the world for number of electric cars. Only last year, as many as 4% of vehicles sold were electric. All this, of course, in order to free themselves from the use of fossil fuels (which the port of Rotterdam is the European and global hub – not in my backyard, one might say) and reduce the environmental and climate impact of mobility.

Since the world began, however, the increase in the availability of a commodity, has increased consumption. So, it can’t be a surprise that the increase in the number of electric cars circulating has grown much energy demand. Moreover, full recharges a car consumes as much as a refrigerator in 40 days. How to cope with such increased demand then? With generators in or off-shore? None of this: to cope with the increased demand, which is expected to grow by as much as 50% in 2030, in the land of the windmills were built three new large coal plants, including two just in Rotterdam (read here and here). Renewable resources are too much more expensive than traditional ones, they say. If then also finding the place for all the generators that would serve, we should add.

So, shortly, in the centre of Rotterdam you can only run with auto zero impact, from the tailpipe, but maximum impact for everything else. Nice…

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When did weather become pathological?

When did weather become pathological? This seemingly trivial question, but instead very interesting, I caught in a retweet of Roger Pielke Sr:

If the source is that fabius maximus, blogger columnist at 360 degrees that often in the climate debate.

First of all, what do you mean by pathological time? Let’s take an example in our own small way. After a couple of good weeks of time absolutely stable and consequent ‘ dead calm ‘ on our country, arrived Sunday on the first thrust of the cold season. Nothing that truly, a beautiful descent of polar air, who promptly received a name, Attila, for those who like such things: rapid fall in atmospheric pressure, storm winds and libeccio maestrale then, swooping and temperatures first dusted with snow even in the Apennines. The acute phase has passed central regions in the night between Saturday and Sunday. The next morning, I turned the comments: rained down a crazy, absurd, wind never seen etc etc. Moreover, soon after, ought to have arrived, the ‘ cold ‘, ‘ cold ‘ air … it should open the doors of the winter, after a long, long season between the equinoxes (that lasts six months from always) that was hot but cooled by water bombs, respecting, of course, of the disease.

The wind crazy, absurd, never seen, arrived between the late evening and overnight. The Fiumicino Airport stations on the coast, and Ciampino, just inland South of Rome, for 2/3 hours respectively gentle breeze at about 50 km/H with gusts to 80 Mph the first and about 40 km/H with gusts to 60 Mph. The libeccio, which comes from the sea, has clearly slowed by friction. A strong wind, of course, but really no big deal. Yet the perception was unanimous, absolutely. And so it is with any rain that arrives every day, hot or cold, to every whim of the time.

In a large scale, i.e. out of our garden, it is that things will go better. We spent all last year waiting for an El Niño ‘ monstrous ‘, which went off before exiting from the cradle. Then, when the seasonal economy has become favorable again, here is the announcement of an El Niño ‘ Godzilla ‘; Although arrived, but, unlike the weather, did not pass and is not expected to exceed any records, if not consumed for ink comment. And no one would notice that El Niño, as his sister La Niña events are random, although cyclical swings of cold and heat on the boundless Equatorial Pacific Ocean waters that beat the rhythm of the tide of that portion of the world and, also, almost everything else on the planet. When there is El Niño, the otherwise arid areas of Central and South America, Western floods are at risk; When there is La Niña, their drought are accentuated and the maritime continent, Australia and Eastern India go under water, with impact on monsoon rains. So goes the climate, from a few million years. But no, now is the time, to heal, to escape or, if possible, to improve, maybe with a nice interplanetary agreement.

WMO, world body up on weather and climate, did you know that this El Niño will be among the most intense of the last 50 years, with illustrious precedents in unsuspected epochs, all right, but now there is climate change and go figure what will happen. What will happen, according to the forecast, is that even this event, as virtually all those that preceded it, will see its peak at Christmas or so (El Niño = child reads the story) then not fall into oblivion, without being released into the atmosphere enough heat to make yet another hot year 2015 between the warm years, with great naturalness but for use by those who want to treat the disease and is preparing to do so in the next December to Cop21 in Paris, with or without Godzilla.

Then the media will comment the misdeeds, experts raise their eyebrows exaggeratedly and everyone else will be there waiting for the pathology we all terms, because, basically, we deserve. All, ominously similar to other and more important facts that are putting at serious risk, those, the fate of the world as we know it. By the way, I wonder if in early December in Paris someone will think that the biggest problem we have is not the temperature …

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We don’t need no education!

It ended the day before yesterday in Rome at FAO headquarters the Science Symposium on Climate. The initiative, which culminated in the issuance of a choral statement, speaks in virtually all of our pages. So, instead of adding more, I thought I’d give it a soundtrack.

You can choose, read the statement or listening to music. Have a nice weekend.

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Ice and rising sea levels, for once it is not worse than expected

The Antarctic Peninsula, on the Western side of the continent, is the only part of the far southern hemisphere where ice is rapidly declining. A possible collapse of the WAIS, West Antarctic Ice Sheet, it says would give a strong contribution to sea-level rise.

So, in the face of projections that in connection with the more pejorative emission scenarios go in the direction of a rise in sea levels of just less than one meter altogether, a group of researchers has developed a method of calculation based on current observations to estimate the contribution of WAIS to this increase. The work has just been released on Nature.

Potential sea-level rise from Antarctic ice-sheet instability constrained by observations

The high-resolution models, writing, require complex calculations to generate ensembles that guarantee to correctly define the level of uncertainty, while low-resolution ones, more affordable, contain parameterizations (hired) too compared to the approximate present observations. It was then chose a different approach from which indicates that the contribution to sea-level rise of the eventual dissolution of the WAIS in relation to emissions scenario more pejorative may be of only 10 cm for 2100 and 2200 cm 72. Their abstract ends as follows:

Our results suggest that the upper extremes of the estimates arising from low resolution models and physical dynamics (up to one meter for the 2100 and a meter and a half for the 2200) are not plausible in respect of correct understanding of physical mechanisms and potential factors triggering processes.

Even here, on Science Daily.

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