Trees' Leaves Grow At a Cool 70° All Over the World

biogeochick writes "Ever turn on the air conditioner on a hot day? How about a heater when it gets cold? OK, so we all know that humans act to keep themselves cool, but what about trees? A recent article on tree core isotopic evidence has shown that trees from tropical to boreal forests all grow at 70 degrees. The study, published in Nature by some fantastic researchers (so one of them is my adviser, so sue me) and covered by NPR on All Things Considered, has shed some light on the convergent temperature at which trees perform photosynthesis." Update: 06/19 21:31 GMT by T : I give, I give -- that's 70 degrees Fahrenheit.

Comments

Or in Celsius

[ObsessiveMathsFreak]

That's about 21.11 degrees Celsius.

Americans really need to start using the metric system. Honestly, it really is worth the effort to switch.

Re:Or in Celsius

[bucky0]

>Honestly, it really is worth the effort to switch.

Really? I'm a physicist and spend all my professional time working in m/s/kg units, but outside of that, what does it matter? We changed over the easier things, but the bit that's left (espcially feet/inches) don't justify the amount it would cost us to retool everything to use metric.

I never did get the obsession other people have with the units we use in the states.

Re:Or in Celsius

[Applekid]

I never did get the obsession other people have with the units we use in the states. It's merely a point of contention for the "we're right, you're wrong" nationalistic crowd. Same with dates: MM/DD/YYYY, DD-MM-YYYY, YYYY.MM.DD, so on and so on.

I'm sure a war or two has been fought over whether toilet paper should be hung in the proper overhand fashion or the grotesque underhand abomination.

Re:Or in Celsius

[vajaradakini]

Yes, clearly everything runs smoothly when people work in different units. Nothing could ever go wrong. Nobody could spend millions on a probe only to smash it into a planet instead, right?

Sometimes it's worth an inconvenience...

Re:Or in Celsius

[Anonymous Coward]

Because it makes it very difficult to communicate things like that with Americans. How would you like it if you did a lot of business with Europe, but they still used cartwheels, furlongs, leagues, and all that stuff? The problem is communication. The rest of the world has seen value in the metric system and switched. But we have a huge problem in a very large country refuses to switch, necessitating the need to artificially extend the life of an archaic system of units.

And for the record, I'm Canadian, living in the US. I STILL haven't gotten a feel for American units, but I'm getting a little better at doing the conversions in my head. That being said, I had no idea what 70F was until googling it.

Re:Or in Celsius

[Hatta]

YYYY-MM-DD(ISO 8601) is the only correct format. When you specify dates in that format, you can sort things chronologically simply by sorting them alphanumerically.

Re:Or in Celsius

[NotBornYesterday]

We buy our milk in gallon jugs, but our soda in 2-liter bottles. However, if you buy soda in quantities less than 1 liter, the measurements switch over to ounces. Every ruler/tape measure/etc. I have had for the past 30 years has been dual-marked with inches and centimeters. Our toilets and urinals are marked "1 gallon / 3.8 liters per flush", and our speedometers are marked in both mph and kph. Engine displacement on new vehicles is noted in liters, while engine displacement on older muscle cars is still noted in cubic inches (as it should be). I have a socket wrench set that includes english and metric sockets.

So, we've been doing pretty well working with both at the same time for years. You mean to say the rest of the world can't keep up? ;)

Re:Or in Celsius

[Pennidren]

The rest of the world really needs to start using only English. Honestly, it really is worth the effort to switch.

Re:Or in Celsius

[Andrew_T366]

I'm generally in favor of metrication and the use of metric units, but the issue of temperature is a key exception. The Fahrenheit scale is more precise, and its zero-to-100 degree range more realistically covers the spectrum of what one would typically see on a weather report.

I sometimes wonder why Celsius is considered a metric measure to begin with: It predates the advent of the modern metric system itself. Its zero-degree reference point is just as arbitrary as Fahrenheit's in the big scheme of things. And, the measure doesn't employ metric prefixes (although I suppose they could conceivably be appropriated for the purpose).

Re:Get a real unit.

[Microsift]

If I recall my chemistry correctly, I think you mean 70 Kelvin, the Kelvin scale does not use degrees.

Re:Shameless karma whore

[LighterShadeOfBlack]

It's got nothing to do with getting upset. It's about sheer convenience. In large swathes of the World the metric system has been the only system taught for decades and this is an internationally read website which has (I suspect) a demographic bias towards younger people. Providing temperatures in a system that large portions of its readers may not know off the top of their head seems silly and unncessary when all that was needed was a "70F (21C)" to save potentially some x thousand readers have to go Google it or, God forbid, read the article.

Re:Shameless karma whore

[Simon Brooke]

And 529.67 rankine for those of us who are simply better looking.

But seriously, when did Fahrenheit stop working?

About the same time that furlongs per fortnight ceased to be a useful measure of speed.

Re:Shameless karma whore

[Daimanta]

"3) 96F - average body temperature"

That's nuts! An AVERAGE temperature to calibrate a thermometer? That's the same thing as calibrating my speedometer in my car to the average speed of a laden swallow.

Re:Shameless karma whore

[Simon Brooke]

The third largest nation in the world (by population) still uses Fahrenheit. I wouldn't consider that quite in the same league.

Which is another way of saying 'less than 5% of the population of the world still uses Fahrenheit'. Looked at that way I'd assert it's in exactly the same league, or, indeed, the same 5.560 kilometres.

Re:Shameless karma whore

[Koiu Lpoi]

Latest System? Are you daft? Celsius has been the standard for science and, well, everywhere except the US, for a long time. Just because the US has been staunchly ignoring the rest of the world's units and measures doesn't mean that it's this newfangled temperature scale only commies and Jews use.

Re:Shameless karma whore

[meowsqueak]

No, you missed the point - Fahrenheit, Celsius, Kelvin, it doesn't matter. What matters is that the unit is *specified* correctly. A 'degree' unit is a 360th of a single complete angular rotation. Obviously a 'degree C' or 'degree F' is completely different.

There's nothing wrong with specifying a non-standard unit, as long as it's specified accurately. Doing conversions is all part of the fun.

Re:Shameless karma whore

[Smidge204]

The worst part is the article says "21 C" - meaning the guy who submitted this had to do extra work to make it that way.

=Smidge=

Re:Shameless karma whore

[cnaumann]

You are missing the elegance and simplicity of using ice water and body temperature to calibrate thermometers. In the 18th century, every thermometer was hand calibrated. Plunge the thermometer into a vat of ice water and make a mark. Plunge the thermometer into your body, make another mark. If you are using ancillary temperature (under the arm) rather than oral or rectal temperature (and really, where would you rather stick that thermometer?), 96 is pretty close. Make 64 evenly spaced marks between the two marks by subdividing by 2 six times. Why not use the boiling point of water? The simple answer is that it is too hot. You would end up with a thermometer unsuitable for measuring outdoor temperatures in a fancy garden, which I imagine were the most profitable sales of the thermometers.

Notice that 32 is also a power of two, and that there are 180 degrees between the boiling point of water and the freezing point.