Is Global Warming real?

[Dioltach]

Personally, I believe that climate change is a thing. Why not? I mean, we've known about ice ages for years, mini ice ages even. And I'm pretty sure human pollution is bad for the environment and needs to be stopped. Are the two linked? I couldn't say, but even if they're not, that's no reason to stop caring about the environment. There are plenty of other things -- poisons and plastic in the seas, smog in cities, deforestation and all its resulting problems -- that we need to sort out, not just the possibility that the current climate change is our doing.

(One thing that always makes me slightly cynical about these things, though, is that the people shouting the loudest warnings are generally the same people who get paid to research the issue. It's in their interests to keep the money flowing in to fund them.)

 

[Umbran]

There is, of course, a larger point to make. The changes generally recommended to combat global warming are, for the most part, changes we should make for other good reasons. Remaining a fossil fuel powered culture is not a good long-term plan.

 

[Dannyalcatraz]

There is also the element that we are currently using petrochemicals for both fuel and man-made materials. We have other increasingly viable energy sources, but the alternate means of producing the myriad plastics we depend on daily are not anywhere near industrial feasibility. It is arguable that petrochemicals are far more important to us as a manufacturing ingredient than as a fuel.

 

[tuxgeo]

And, don't all the best lies not have some basis of truth in them? There is a "nugget of truth" in Jurassic Park, too. There are actually mosquitoes trapped in amber. That doesn't mean we can have T-Rexes wandering around eating people. . . . < snip there >

A newly-released paper reports the major portion of an intact salamander (missing one leg) found trapped in amber in the Dominican Republic. (The link is to Daily Mail UK, which may be helpful if you trust them for news.)

 

[Umbran]

A newly-released paper reports the major portion of an intact salamander (missing one leg) found trapped in amber in the Dominican Republic. (The link is to Daily Mail UK, which may be helpful if you trust them for news.)

That's fine. The half-life of DNA, even in bone or trapped in amber, seems to be about 520 years or so. A 65 million year old dinosaur cell has gone through about 125,000 half-lives. Thus the amount of DNA has been cut in half 125,000 times, leaving nothing useful.

 

[Janx]

That's fine. The half-life of DNA, even in bone or trapped in amber, seems to be about 520 years or so. A 65 million year old dinosaur cell has gone through about 125,000 half-lives. Thus the amount of DNA has been cut in half 125,000 times, leaving nothing useful.

This might be a good question for the Physics AMA, but if the half life of DNA is 520 years, how does a tree get to be a 1000 years old?

 

[Thunderfoot]

I have to say that our current activity - using a computer, smartphone,etc to convey information is the largest usage of petrochemicals known to man, why because all of these things utilize plastics and polymers that are developed from the refinement of oil - want to save the universe or at least your home in it, turn off your computer, go off the grid and live off the land. Oh, wait you're a non-hunting, non-fishing progressive farming vegan? Then you're screwed I guess.

My problem with this problem is that people in cities (the largest cause of all things pollution) tend to turn their noses up at those in the rural areas where we live day to day a lot closer to the "old ways" and yet are looked at as "savages" because we don't ride our bikes to work, well when work is 25 miles away, that's just not possible. Look at yourselves first city dwellers, leave us hicks alone. (Keep in mind I lived almost 20 years in the DC - Baltimore metro area so I know of what I speak regarding urbanites)

 

[Morrus]

This might be a good question for the Physics AMA, but if the half life of DNA is 520 years, how does a tree get to be a 1000 years old?

How does the half life of DNA prevent that? The life span of an organism has nothing to do with the half life of DNA.

 

[tomBitonti]

We can ask the same question of any propogation of DNA: Everyone's DNA has been passed down and copied, millions of times, over a couple of hundred million years.

It certainly hasn't stayed the same for all that long, but (I thought) it has been mostly stable for the last few thousand years.

A part of the answer, I think, is that during reproduction, a culling of bad copies is made (that being that non-viable copies don't survive).

Also, living cells have repair mechanisms for DNA. Is the quoted half-life for DNA in a living cell?

Here is a nice starting point for DNA repair:

http://www.ncbi.nlm.nih.gov/books/NBK9900/

DNA, like any other molecule, can undergo a variety of chemical reactions. Because DNA uniquely serves as a permanent copy of the cell genome, however, changes in its structure are of much greater consequence than are alterations in other cell components, such as RNAs or proteins. Mutations can result from the incorporation of incorrect bases during DNA replication. In addition, various chemical changes occur in DNA either spontaneously (Figure 5.19) or as a result of exposure to chemicals or radiation (Figure 5.20). Such damage to DNA can block replication or transcription, and can result in a high frequency of mutations—consequences that are unacceptable from the standpoint of cell reproduction. To maintain the integrity of their genomes, cells have therefore had to evolve mechanisms to repair damaged DNA. These mechanisms of DNA repair can be divided into two general classes: (1) direct reversal of the chemical reaction responsible for DNA damage, and (2) removal of the damaged bases followed by their replacement with newly synthesized DNA. Where DNA repair fails, additional mechanisms have evolved to enable cells to cope with the damage.

Thx!

TomB

 

[Ryujin]

Personally, I believe that climate change is a thing. Why not? I mean, we've known about ice ages for years, mini ice ages even. And I'm pretty sure human pollution is bad for the environment and needs to be stopped. Are the two linked? I couldn't say, but even if they're not, that's no reason to stop caring about the environment. There are plenty of other things -- poisons and plastic in the seas, smog in cities, deforestation and all its resulting problems -- that we need to sort out, not just the possibility that the current climate change is our doing.

(One thing that always makes me slightly cynical about these things, though, is that the people shouting the loudest warnings are generally the same people who get paid to research the issue. It's in their interests to keep the money flowing in to fund them.)

Those people stand to make a lot more by supporting industry, than they do by supporting the side that would shut industry down. Research dollars come from people who stand to make money by funding said research, or from government. When it comes to governments, the Government of Canada has been actively muzzling scientists who speak out against things like The Tar Sands and climate change.