Venus Express reveals the complex cloud patterns of our neighbouring planet

For earthbound sky watchers Venus is the bright star that chases the Sun below the horizon in the western evening sky. When it comes to scientific knowledge of our neighbouring planet, popular accounts often paint a Dantean picture of a fiery cauldron with a crushingly dense atmosphere.

Ultraviolet image of the southern hemisphere of Venus, taken by the VMC instrument onboard Venus Express. The picture was taken from a distance of 30,000 km from the surface, and shows how the planet’s clouds change from spotty and fragmented at low-latitudes, to streaky at mid-latitudes, and hazy around the poles.

That hellish vision is part of the story, but only with the European Space Agency’s Venus Express mission have we come to appreciate the complexity of a world which like Earth is meteorologically active. On 11 April 2010 Venus Express will have been four years in orbit around the planet, and during that time the mission has provided much scientific insight into the Venusian atmosphere.

Orbiting close to the Sun, Venus is subject to intense heating, and this leads to a dynamic atmosphere. We have long known that Venus is covered with dense clouds rich in sulphuric acid. Now, with observations down to a few hundred metres’ resolution from the Venus Monitoring Camera (VMC) and VIRTIS thermal imaging spectrometer onboard Venus Express, we have learned that the clouds range from fragmented patches around the equator, covered with a bright lace of sulphuric acid droplets, to an almost featureless haze high above the poles.

The equatorial patchwork of clouds is due to vigorous convective heating of discrete parcels of air in the region where most of the incoming solar energy is deposited. At mid-latitudes this mottled cloud pattern gives way to streaky, banded shapes, providing evidence of more laminar atmospheric flow. The transition between these two regimes is one of the outstanding questions in our understanding of the atmosphere of Venus.

Perhaps the most spectacular cloud feature observed by Venus Express is an ‘S’-shaped polar vortex around 1500 km across, which appears to be part of a global vortex-like organisation of the planet’s atmosphere. The feature rotates around the south pole at latitudes above 70 degrees, with a period of around two Earth days. On a planetary scale, clouds on Venus extend upwards from around 45 km altitude; the cloud top at low- and mid-latitudes is located at about 75 km altitude, descending to 65 km in the eye of the polar vortex.

By analysing light from stars as they set through the atmosphere of Venus, the SPICAV spectrometer on Venus Express has revealed that the night-side cloud layer extends up to 90 km altitude in the form of an opaque haze, and another 15 km on top of that as a transparent haze. Ozone is present at higher altitudes.

In October of last year the European Space Agency extended the Venus Express mission to the end of 2012, allowing for some overlap in time with the Japanese Planet-C spacecraft. It is expected that the complementary approaches of the two missions will lead to further major discoveries about the atmosphere of Earth’s sister planet.

Further reading

Titov et al., “Venus express: Highlights of the nominal mission”, Solar System Research 43, 185 (2009)

“You’re my bitch now, Mr Seidenfaden!”, says Saudi lawyer Faisal Yamani.

Denmark’s once respected broadsheet newspaper Politiken yesterday lost its battle with journalistic integrity, and gave up the ghost in a deep sigh of petite-bourgeois liberal angst. The funeral will be a private affair, attended only by a small number of shame-faced hacks and members of the Copenhagen chatterati who would rather not be photographed, let alone quoted.

The newspaper’s demise was precipitated by an apology from the editors for their re-publication in 2008 of the infamous Mohammed cartoons. Denmark’s government is not particularly pleased by the latest development.

In other pages, Politiken declares that a former editor spied for the Zionist Entity. Stories about Danish Jews disembowelling København kittens for fiddle strings will no doubt follow.

Go on girl, give the cheeky sod a slap!

He’s asking for it.

In grave tones the British Library warns that Britain’s “online heritage” could be lost forever if the government does not grant it a “right to archive”, similar to that which governs print publications. Britain’s official über-library has since 2004 been archiving UK websites, but has so far succeeded in covering just 6,000 of an estimated eight million sites.

The British Library complains that it must obtain the permission of website owners before archiving them…

“We’ve got the know-how but we need the rules to say we don’t need to ask permission… We’re archiving for the nation rather than commercial gain.”

Set aside for one moment the emotiveness of the second statement, and focus instead on the factual inaccuracy of the first. Neither the British Library nor anyone else requires authorisation to archive historical snapshots of public websites. As is shown by the private but non-profit Internet Archive (aka WayBack Machine), it is up to site owners to opt out if they do not want their content archived. They do this by placing a simple instruction code in a file named robots.txt. This blocks the WayBack Machine’s software robot from trawling the site.

One has to ask why the British Library wishes to archive websites, and how often it intends to take snapshots of their content. This is not evident from the press release that accompanies the launch today of the library’s “UK Web Archive”. If the British Library seeks to fossilise websites that record “major cultural and social issues”, then its operation should be restricted in scale, with no talk of archiving eight million sites. The Library should instead concentrate on collaborating closely with the owners of websites of significant UK interest, and for these online publications expand on the work of the WayBack Machine.

If, on the other hand, the intention is to archive everything, the question is: why bother? Surely there is no point in collecting daily snapshots of, say, every FaceBook page and ranty blog. Unless it is simply an exercise in creating work for work’s sake, and providing circular justification for the digital side of the British Library’s otherwise worthy endeavours.

But there are deeper, more philosophical issues raised by initiatives such as the WayBack Machine and UK Web Archive.

Digital information is not a physically conserved quantity. That is, there is no universally fixed amount of digital information. Bits and bytes are created as required, and can be destroyed without violating any fundamental law of physics. Digital information is growing at an exponential rate, and much of it is redundant. Useless information.

We are rapidly evolving into a society that employs vast networks of sensors to record and monitor our environment. CCTV cameras watch our public comings and goings, stress sensors monitor the movements of buildings, bridges and vehicles, and gargantuan scientific projects such as the Large Hadron Collider collect billions of data bits every second.

Before long it will become impossible to archive for posterity all the world’s digital data. It may be less of a challenge to file away website content, but the principle remains the same. There is no point in collecting information unless it has demonstrated value.

The British Library’s mistake is to treat online digital data as being in essence the same as words on a printed page. They are not.

It’s a strong statement, made by Nanjing ecologist Xiong Zhenqin, that defines the world’s most popular Internet search engine as one of a jobbing scientist’s bare necessities. But, if we are honest, many of us would have to admit our dependence on Google. There may be other options, but Google is the dominant player in the market, and the most powerful search engine with the infrastructure required for truly global reach.

A survey to be published tomorrow in Nature reveals that Chinese scientists would be royally screwed if Google was to follow through on its threat to pull out of China. Of the nearly 800 scientists who responded to the survey, over three quarters said that Google is their primary search engine. More than 80% use Google to find academic papers, around 60% to gather information on other research programmes, and a third for science policy and funding news.

If the same survey were carried out in Europe or North America, the results would likely be very similar. Western universities may have greater access to scientific journals, but from what I can see we are all turning to electronic searches, at least in the first instance. Web searches save time, and allow us to digest vast volumes of data. And for those without access to academic libraries, life without Google would be inconceivable.

The question of Google’s involvement in China, and its relationship with the Chinese state, is a difficult one. I tend to the view that Google should withdraw from China unless all content filtering by the authorities there is removed. At the same time, however, I realise that it’s not an easy call for the company to make, or one that would necessarily have the desired effect. This is a point emphasised by Guobin Yang, an Internet researcher at Barnard College in New York City:

“People have been largely focusing on how the filtered content has limited access to certain information. But Google’s presence has also helped the development of civil society in China.”

This is, says Yang, because Google equips citizens with the information they need to be more politically active. Where else are they to obtain this information, and how much of the Internet is beyond reach to most Chinese citizens?

That is also a difficult question to answer, as the so-called ‘Great Firewall of China’ is a software filter that must necessarily operate with minimal human intervention. In the not-so-distant past, for example, this website was blocked in China, yet today it appears to be uncensored, despite there being a number of comments critical of the Chinese state. Totalitarianism can never be total in the age of global electronic information.

As for Google’s moral and ethical responsibilities, doing no evil is not as simple as it sounds.

Further reading

Jane Qiu, “A land without Google?”, Nature 463, 1012 (2010)

“He wasn’t a murderer. He wasn’t a thief. He wasn’t a rapist. He was simply a young man who wanted a better future for Cuba.” [Laura Pollan, Ladies in White]

RIP Orlando Zapata Tamayo – plumber, democrat, dissident, prisoner of conscience.

It may be a little stronger than the metaphorical flapping of a butterfly’s wings in Brazil causing a hurricane on the coast of Australia, but the localised Pacific Ocean climate pattern known as the El Niño-Southern Oscillation is associated with floods, droughts and other severe weather effects throughout the world, and affects the livelihoods of millions of people.

You may have heard of El Niño as a result of the complication it adds to global climate models. Resolving such modelling difficulties requires an accurate knowledge of local sea-surface temperatures and wind speeds, with which we can better predict El Niño and associated La Niña events. The problem is that advance warning has so far been limited by a predictability barrier which is the northern hemisphere spring.

According to Tokyo University climatologist Takeshi Izumo and others, that difficulty could be overcome with a better understanding of the Indian Ocean Dipole – an oceanographic phenomenon which leads to an oscillation in sea-surface temperatures roughly every other year between the western and eastern waters of the Indian Ocean. For example, the positive phase of the oscillation, with warmer waters in the west and a corresponding cooling in the eastern Indian Ocean, leads to droughts in Indonesia and Australia. Conversely, the negative phase, with warmer waters in the east, causes cooler and drier conditions in the west. In addition, the Indian Ocean Dipole has a major effect on monsoon rainfall over the Indian subcontinent.

The Indian Ocean Dipole is linked to the global climate, and interacts strongly with the El Niño-Southern Oscillation. In their Nature Geoscience paper, Izumo and colleagues show that the negative dipole phase tends to be followed by an El Niño event more than a year later, and the positive phase leads a La Niña event by a similar period. The proposed physical connection is based on rapid changes in sea surface wind speed in the Pacific following the decay of a dipole event in the Indian Ocean during the northern autumn or winter.

It is this link between the Indian Ocean Dipole and El Niño-Southern Oscillation which provides a bridge over the spring predictability barrier for El Niño events. A better understanding should come from detailed observations of the response of the Indian Ocean to monsoon wind patterns.

Further reading

Izumo et al., “Influence of the state of the Indian Ocean Dipole on the following year’s El Niño”, Nature Geoscience (2010)

1. Forward…

British MPs call for public funding of homeopathy to be withdrawn.

2. Back…

Andreas Moritz – “a medical intuitive; a practitioner of Ayurveda, iridology, shiatsu, and vibrational medicine” (i.e., a new-age wanker) who believes that cancer “does not kill a person afflicted with it!”, and makes part of his living from selling various snake-oil concoctions – is out to silence critical bloggers and scientists.

Andreas Moritz is a very stupid man.

Stir the mixture well
Lest it prove inferior,
Then put half a drop
Into Lake Superior.

Every other day
Take a drop in water,
You’ll be better soon
Or at least you oughter.

William Croswell Doane (1832–1913) was a witty man.

Further to the recent kerfuffle over a Christian priest who breaks bread with antisemites, the victim of that spat, one Joseph Weissman (aka “Seismic Shock”), writes on his own blog and also over at Harry’s gaff about Stephen Sizer’s attempt to portray himself as an opponent of the current regime in Iran. This when the anti-Zionist theologian and occasional pastor to the well-healed of the Surrey stockbroker belt is in fact right up the Khomeinist collective arse, and thus morally as well as intellectually compromised. Weissman’s 10 numbered points are worth reading in full.

We turn our attention now to fools.

Roger Pearse – scholar of patristics and defender of Stephen Sizer – was the subject-victim of one of my blog posts from three weeks back. Since then he has popped up in the comments following a few other posts.

Following his contribution to my recent reflection on Augsburg bishop Walter Mixa’s bizarre views concerning priestly paedophilia, Pearse was banned from commenting on this blog. The straw that broke the camel’s back was Pearse’s insinuation that the much respected human rights campaigner Peter Tatchell condones the sexual abuse of children.

Following the ban, Pearse tried to leave another comment, in which he accused me of threatening him. “Do your worst!”, he said. That so-called threat can only be my stated intention to inform Tatchell of Pearse’s libellous comments; there has been no communication between me and Pearse other than in the comments published on this site and his blog.

If this were not silly enough, Pearse yesterday gave voice some quite frankly paranoid thoughts about malice on the Interwebs. It is entirely conceivable that I am the “someone rather unpleasant online who started threatening me”.

Pearse has now removed all contact details other than his Google email address from the whois database, contrary to ICANN rules which state that owners of .com domains must be traceable through that publicly-accessible database. There is no need to include one’s home address, but it must be possible to trace a site owner through a whois search. But Pearse is surely aware that it is always possible to trace a website owner through the domain registrar, in cases where actual or potential legal action is involved.

This is all very peculiar, as Pearse has on his own blog made scathing reference to anonymous blog commenters, yet seems unwilling to be accountable.

Am I missing a trick here, or is Roger Pearse lacking something altogether more vital?

I always wince when I see the term “Kindemissbrauch” in German media. In my mind I automatically translate it literally as child misuse, with all its euphemistic connotations.

This time it’s from a story in yesterday’s Tagesspiegel about the bizarre explanation given by Augsburg bishop Walter Mixa for child sex abuse by catholic priests and religious. The latter is a term used for non-ordained monastics. Mixa was referring in particular to a big scandal in the German church surrounding the widespread abuse of students in the Canisius Jesuit-run high school in Berlin.

What’s happening, you see, is an aftershock of the 1960s “sexual revolution”, which has affected the sacred as much as it has the profane. Or at least that’s the bishop’s interpretation. It’s worth recalling that last year Mixa linked Nazi and Communist crimes against humanity with atheism, saying “a society without God is hell on earth”. He also quoted Dostoyevsky (“If God does not exist, everything is permitted.”), and pleaded that Christians are persecuted.

Well, at least Mixa is being true to his sophist form, I’ll give him that. Intellectual self-consistency is all-important when it comes to Holy Mother Church.


Catholicism covers a multitude of sins.

Hat tip: Anja