No propaganda please

Ooh, looky here!  Some Aussie cannabis activists have unearthed an interesting study from 2006! Check this shizz out:

Active component of marijuana and Alzheimer’s disease pathology (Hereafter: Eubanks, et al. 2006.)

Yeah, umm, the most excitable of the pro-pot people are jumping on this study as indispootaple proof that cannabis cures/treats/manages Alzheimer’s disease.

Now, I’m for the legalisation of marijuana; but I happen to think that propaganda is self-defeating and destructive, so I’m very much against enabling propagandists who otherwise agree with me on certain issues. That means that sometimes, correction is called for.

Alzheimer’s disease is a currently incurable affliction that slowly kills neurons in many parts of the brain. The first brain structure that Alzheimer’s attacks is the hippocampus, which is where memories are encoded, and this is why most people associate the condition with the dramatic memory loss.

Alzheimer’s presents with catastrophic cell death (obviously) and higher-than-normal levels of amyloid plaque deposits in certain regions of the brain. In healthy people, the death of neurons and the presence of large deposits of amyloid plaque is often a consequence of ageing, but in Alzheimer’s, these harrowing symptoms occur much more rapidly and extensively.

(Click here for a refresher on neurons.)

The study found that pot seems to inhibit the activity of an enzyme called acetylcholinesterase (AChE) in the brain. AChE breaks down unused acetylcholine at the synapse (the inconceivably tiny space between the axon terminal of one neuron and the receptors of another). Acetylcholine is an extremely important neurotransmitter (a chemical signal that affects the polarisation of the receiving neuron, which either provokes or inhibits an action potential); but like anything good, you don’t want too much of it; you need a balance. That’s where AChE comes in.

When AChE activity goes a bit overboard (often due to genetics), excessive accumulations of amyloid plaque start to develop in the brain. This process is called AChE-induced amyloid beta-peptide aggregation. When amyloid beta-peptides a synthesised in healthy brains, they protect against oxidative stress, help regulate cholesterol transport and do other non-threatening thngs; but once again, too much of a good thing can be bad news. Large deposits of these peptides can also result in inflammation, and as above, a brain afflicted by Alzheimer’s is riddled with them.

But correlation does not imply causation. According to the amyloid hypothesis, Alzheimer’s disease is caused by this build-up of brain plaque. This hypothesis doesn’t really hold, though, because a vaccine that clears amyloid plaques was developed and trialed. During stage I trials, it was found that the clearing of amyloid plaque did not have a significant effect on the onset of dementia.

Thus, the thing that cannabis does especially well will reduce the development of a neurological marker of Alzheimer’s disease. Clearly Alzheimer’s is related to amyloid plaques, but we still aren’t sure how. So it would be premature to suggest that this function of cannabis could play a part in the treatment of Alzheimer’s disease.

As I said above, AChE inhibition does mean that more acetylcholine will be present in the synaptic gap during neurotransmission. A little extra acetylcholine is associated with boosts in cognition; so the inhibition of AChE is one way to boost cognition. There are already drugs on the market, and such drugs (like Exelon) are often used to slow the progress of Alzheimer’s disease. So could pot do that too?

Well, no. Cannabis is quite different.

Acute intoxication with cannabis comes with a disruption of short-term memory for as long as the high lasts. This effect is due to the inhibition of the release of neurotransmitters, including acetylcholine, in the hippocampus. In fact, researchers have remarked that the extent of neural inhibition in the hippocampus for the length of the high actually resembles a temporary hippocampal lesion.

The consumption of too much pot over the long term does make you stupid. Worse, doses of marijuana to equal doses of similar drugs used in Alzheimer’s treatments would lead to THC-induced hippocampal deterioration, which is what Alzheimer’s disease does on its own. Moreover, if you read Eubanks, et al. with a fairly comprehensive dosage chart handy, it’s clear that you would have to consume a heavy dose of THC in one session to achieve a substantial inhibition of AChE enzymes. No, that’s not a challenge.

So the cannabis you smoke actually won’t do shit for Alzheimer’s patients. It’s kinda like pouring a little bit of gasoline on a house fire.

But targeted drugs derived from cannabis might. Even so, the work of Eubanks, et al. offers no argument in favour of legalising cannabis. To claim it does is simply misleading.

So can we stop pretending that cannabis is some kind of magical wonder drug suppressed by Big Pharma? It’s not. It’s just a relatively safe recreational drug with some notable medicinal uses. That should be our platform.

Now, don’t get me wrong: if you live in my state, join that group and support them. (It should go without saying, but: you don’t have to be a pothead to support legalisation. I’m not a user, I just happen to believe that proscribing a victimless source of pleasure while tolerating more destructive sources of pleasure is simply wrong.)

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In Memoriam: Hitch

Hitch

Christopher Eric Hitchens (April 13, 1949 – December 15, 2011)

On paper, Christopher Hitchens was a first-rate journalist and an incisive, brilliant polemicist. In reality, he was so much more. A lot has been written on his life already, so I’ll keep it short and personal.

Hitch was one of those rare individuals who not only refused to mince words, he refused to mince facts. His opinion was always his opinion, invariably built on the most compelling facts he could unearth. His opinions on specific issues might have echoed those of figures as diverse as Leon Trotsky and George Bush Jr., but with Hitch it was always clear such overlaps were merely happenstance. He was the anti-stereotype; he never played into partisan lines.

His debating partners knew him as a staggeringly erudite, witty juggernaut. Hitch never compromised, but he rarely counted his ideological opposites among his foes. Even so, he had the unique ability to profoundly respect the individual, while vehemently declaiming whatever loathesome ideas came out of their mouth. Though he was a ferocious contrarian (despite his ironic discontent with the label) and an unrivalled rhetorician, by all accounts, he was also a gracious and affable gentleman.

I never had the privilege to meet Christopher. I knew him through his writing. Discovering his work was a pivotal thing for me. The genesis of this blog can be traced back to 2009, when reading Hitch for the first time rekindled my passion for writing, which ultimately got me out of a deep, dark hole I’d found myself in, plagued with poorly-managed depression and self-loathing. He spoke to what was left of me. Here was a writer none could categorize; who wrote passionately and selflessly, and who wrought beautiful prose. Here was someone for me to look up to; not slavishly, of course (he would have hated that), but as a mentor. And he delivered.

Listening to Hitch speak sparked a revolution in my mind. I had long considered myself an atheist and a freethinker; the former position was facile for me to adopt (‘atheism’ merely gave a name to a pre-existing conviction), but before Hitch I plainly failed at the latter; I was comfortable in my 21st century Green-voting inner-east Melbourne ideological mould. Hitch taught me to pull back the curtain, to always ask the hardest questions and to always demand answers.

Hitch also taught me that one should change one’s mind when the facts demand it. His constant struggle against the one answer, the divine plan, the totalitarian final word, is one we are obliged to continue. And most crucially, nothing he did was ever boring.

He was brave on and off the page; he once openly defacing a sign sporting fascist propaganda in Beirut. Following the subsequent assault he endured at the hands of a pack of far-right thugs, he remarked to his colleague Michael Totten: “I think a swastika poster is partly fair game and partly an obligation. You don’t really have the right to leave one alone.”

There’s very little that flowed from Hitch’s pen that I didn’t find enlightening, but I particularly relished the things I disagreed with. It felt like an achievement to have independently conceived a carefully-considered position contrary to his. One couldn’t simply go to his critics, because they were too often right for the wrong reasons; it was rare that Hitch didn’t anticipate and demolish such (generally obvious) arguments head on. As such, disagreeing with Hitch was hard work.

Now I always look for a glimmer of Hitch’s daring when I assess the work of other writers. He plainly set the benchmark high, and precious few will ever make the cut. I’m not ashamed to admit I aim to cultivate Hitch’s remarkable lucidity, flare and audacity in my own prose. (It must be acknowledged that his trademark style is inimitable and all attempts to replicate it will fail, so I won’t be doing that.) I don’t feel I will ever do his influence on me justice, but I’ll sure as shit try.

Hitch had no need for a superstitious afterlife; his prodigious oeuvre had long ago cemented his immortality. I have no doubt his books will be devoured by independent thinkers for many generations to come.

Thank you Christopher. Thanks for showing me the courage to write exactly what’s on my mind. Thanks for cajoling me into standing up for what I think is right. Thanks for the laughs, the serious stuff and the life lessons. You will never be forgotten, and you are sorely missed.

Take the risk of thinking for yourself. Much more happiness, truth, beauty, and wisdom will come to you that way.

—Christopher Hitchens

Click here for Slate’s compendium of Hitch’s greatest hits.

Good news on global warming (maybe)

‘Good news’ is an odd thing to associate with ‘global warming’; it just sounds wrong. As implied though, my association is strictly tentative. In addition, even if true, it might prove to be a slight exaggeration. Hopefully the strength of my association solidifies with time.

I’m consistently frustrated and perplexed by persistent assertions from the denier camp that those of us who recognize the benefits of science apparently relish the idea of anthropogenic global warming. Not so, and no one should need to spell it out like that.

I’ll grant that the Greenpeace crowd seem to, but they’re an unsophisticated minority and many of us find them tedious. I think the Greenpeace claque are insane. I believe that most of their positions are catastrophically counterproductive, not just politically, but also environmentally.

(Libertarian) writers like Matt Ridley and Michael Shermer have indicated that while they accept the basic science of global warming, they don’t believe it will lead to the nightmare scenario that the – well, let’s just call them ‘leftists’ – have been making noises about. (Call Ridley and ilk ‘lukewarmists’, they hate that.) According to a recent article in New Scientist, some of these more sophisticated ‘sceptic’ cadres may not be totally disappointed. If so, I couldn’t be happier for them.

A study lead by Andreas Schmittner (of Oregon State University) has indicated that the global climate might be slightly less sensitive to atmospheric CO2 concentrations than what previous data bore out. The authors of the actual paper, published in the journal Science, have themselves described many of their study’s limitations. And, for the sake of the more stupid elements in the media, stressed that atmospheric CO2 levels still do contribute significantly to warming.

The paper described efforts to probe climate sensitivity to atmospheric CO2 concentrations using model calculations based on temperature reconstructions of the Last Glacial Maximum (LGM) ice age, which occurred around 20,000 years ago.

A major pitfall in this study was that it only used one climate model to calculate the data. For these findings to affect consensus, they would need to be replicated in several other models used by climatologists. The model used, UVic (of the Canadian Centre for Climate Modelling and Analysis, or CCCMA) has been criticized before by scientists for being overly simplistic. In 2010, Tamino found that CCCMA models were failing to reproduce 20th century temperatures. I also noted that the paper didn’t cover the more complicated ancillary factors like ocean acidification.

Another shortcoming of the study that struck me (elucidated in Skeptical Science’s very detailed commentary) was that the mean temperatures assigned to the LGM for the purpose of the study was significantly higher than most paleoclimate estimates.

According to the study, the average global temperature during the LGM was only 2.6 Kelvin cooler than the current global temperature. Mainstream estimates of mean LGM temperature, based on temperature reconstruction data indicate that the period was roughly 4-7K cooler than the current global temperature. Notably, climatologist Gavin Schmidt told New Scientist:

A different model would give a cooler Last Glacial Maximum, and thus a larger sensitivity.

According to Skeptical Science: if this study holds up, it not only constrains the more terrifying predictions of other models, it also constrains many of the deniers’ staple hypotheses such as low climate CO2 sensitivity and negligible warming. New Scientist quotes Schmittner:

Very small changes in temperature cause huge changes in certain regions, so even if we get a smaller temperature rise than we expected, the knock-on effects would still be severe.

If you are interested in the finer points of the paper, check out the commentary on Skeptical Science, linked above. Much of what I’m discussing here is covered in much greater detail there.

In the paper, the authors described a number of their own caveats, then added:

Until the above questions are resolved, it’s premature to conclude that we have disproven high climate sensitivities, just because our statistical analysis assigns them low probabilities.

As usual, different news sources have framed the findings in different ways. A Google News search for “Andreas Schmittner” yielded the following:

  • CO2 sensitivity possibly less than most extreme projections (Los Angeles Times)
  • Global warming much less serious than thought – new science (Register – the URL contains the similarly optimistic character string ‘runaway_warming_unlikely’)
  • Carbon dioxide doubling impact has limit (USA Today)
  • New global warming estimate (Sydney Morning Herald)

The last one is my favourite. After yesterday’s sojourn with bullshit, I’ll try to keep the meta-journalism to a minimum.

My least favourite article dealing with these findings was posted on Anthony Watts’ popular internet AGW denier den Watts Up With That? The post is entitled “New study in Science shows climate sensitivity overestimated”. To wit:

Their estimate is 2.4C for a doubling of CO2 (sic), which is still higher than Spencer and others have estimated but significantly lower than IPCC’s projections.

Skeptical Science keep a modest catalogue of rebuttals specific to Watts and a more meaty one for his pal Roy Spencer. It always amuses me to read prolific deniers cherry-picking from a vast and exponentially accruing pile of scientific papers on climate change and justifying their selections with diminutive preambles. Once again, consider the bottom of the barrel clean.

Most scientists believe that a temperature rise of more than 2K is too dangerous to allow, because it risks runaway feedback-activated global warming. This experiment predicts that if carbon-intensive power generation and infrastructure continues to emit unchecked, we can still expect more than 2K warming.

As Schmittner himself told Science Daily:

Hence, drastic changes over land can be expected. However, our study implies that we still have time to prevent that from happening, if we make a concerted effort to change course soon.

So it could fairly be said I exaggerated when I said that this study potentially brings good news. Maybe we’re merely dealing with potentially less-bad news. If  any good news comes out of this, it will be that, if true, we might have more than five years to prevent a global disaster (to put it mildly); but obviously that depends on us.

Who are the real sceptics?

Did you hear about this Climategate 2.0 bullshit? Why are journalists not getting fired for all this ridiculously irresponsible misreporting?

Over the last couple of days, we’ve been graced with the news that 5,000 personal emails exchanged by climate scientists have been leaked to the public. These aren’t recent emails, mind you, these emails cover the same time span as those released in the last ‘shattering’ leak. So hack journalists and parties with vested interests are forcing us to discuss yesterday’s news today.

The mass media is once again doing the public a gross disservice through an unbridled flexing of staggering incompetence. Many reporters are defiantly refusing to even look beyond the now infamous text file (itself consisting almost entirely of shamelessly mined quotes) when writing their stories. What makes this myopia so damning is that in most cases, a fucking glance at the actual email the mined soundbite came from will lay the context bare – effectively refuting the entire article.

There are countless examples of such vacuous hype on Google News. No doubt you’ve already seen some. If you haven’t, you can start with this gem (shared courtesy of none other than Rupert Murdoch’s own glorified histrionic soap box). All we have here are the veritable peacocks of mindless dogmatism splaying dazzling shows of confirmation biases in defence of their stock holdings.

Even the better articles succumb to the deluded trap of giving ‘the opposition’ a voice on matters of science. If high school science was taught the same way, it would sound something like this: “That’s chemistry for today, class; now don’t be late for alchemy after the break!”

You have to stand in awe at the scandalous behaviour of these so-called ‘journalists’. I would love to see a dump of their leaked email exchanges. This is intellectual suicide at its most intrepid.

What can’t be disputed is that the the biggest sceptics of man-made global warming appear to be the scientists themselves, and that’s the way it should be. This is how science is done. We wouldn’t know that the planet is warming if no one tried to disprove it. Thankfully the scientists attack the anthropogenic global warming hypothesis at every angle, and they do so thoroughly; and to our collective despair, AGW has repeatedly proven itself bulletproof.

Frankly, it warms my heart to read about scientists critiquing their colleagues’ work ruthlessly. I like my scientists second-guessing themselves. I also like them doing what they can to stamp out any interference in their research by the militantly ignorant.

Only a public horribly ignorant of the methods of science could possibly be taken in by such a travesty of lazy, biased reporting.

The timing of the leaks is obviously calculated to disrupt the upcoming UN climate change conference in Durban. Representatives of developing countries already affected by global warming are considering ‘occupying’ the talks to try to push for an international action plan. That this isn’t getting more coverage alongside the leaks is another media scandal.

With each new piece of data in the public sphere, I find myself even more dumbstruck by the sheer selfishness of the denier project. Irresponsible reporting makes journalists part of the problem. It’s no wonder that journalists are the least trusted group of professionals in Australia.

That a few people seem to think climate scientist Phil Jones is an incompetent dick is hardly newsworthy, and it says a lot less about the validity of climate science as a whole. Phil Jones has already responded to the latest leaks.

Have the media already forgotten that massive independent study – funded by deniers – that was published last month and showed unequivocally that the planet is inarguably warming? Earlier this month, more data was released indicating that we only have another five years to drastically cut our greenhouse gas emissions if we want to avert catastrophic global warming.

The current fixation on what was happening in the world of climate science last decade is also plainly ridiculous. Science isn’t static. Anyone who thinks it is simply doesn’t know anything about science, and therefore isn’t qualified to make credible comments on the work of scientists.

It’s also interesting to note that the contents of the dump totalled at around 5,000 emails. Perhaps the most brazen demonstration of the stupidity of the leakers isn’t that they intentionally quote-mined emails they released alongside the original emails, but that they added this little nugget to their maliciously deficient little text file:

The rest, some 220.000, are encrypted for various reasons.
We are not planning to publicly release the passphrase.

Why the fuck not? I’m sceptical; I want to know these ‘various reasons’. They saw fit to include emails containing little more than holiday greetings and similar banalities. How do these disingenuous tools decide on which emails to withhold? 220,000 emails is an awful lot to withhold.

Even the worst of the so-called deceptions alleged to have been perpetrated by the scientists at the centre of the current propaganda campaign are nothing on those perpetrated by their denialist detractors. I covered some of these demonstrable crimes in my defence of the science behind anthropogenic global warming, which you can read here.

Urgh.

I invite you to look through the emails themselves here. There is a remarkable preponderance of no absolutely evidence of scientists trying to mislead the public. In fact, they appear to have been making every effort to not mislead the public. I know, right?

You can read some worthy coverage here and here.

Update: Check out the RealClimate team’s responses to this whole drama here. (Link thanks to the amazing Tamino.)