Berkeley CSUA MOTD:2009:May:27 Wednesday <Tuesday, Thursday>
Berkeley CSUA MOTD
2009/5/27-6/3 [Science/GlobalWarming] UID:53048 Activity:low
5/27    Paint your roofs white.
        "Making roads and roofs a paler colour could have the equivalent
        effect of taking every car in the world off the road for 11 years,
        Chu said."
        \_ Did that already.  Already noticed the house is much cooler.
           Have not needed cooling even though highs were 90F.  --PeterM
           \_ I've been telling my wife we should do this, and she thinks I'm
              crazy.  Now that the energy secretary agress with me, maybe I can
              finally do it.  What kind of paint do I need for painting roofs?
              Is it just the same kind of paints as for exterior walls?   -- OP
              \_ I actually didn't paint it--I changed roofing materials from
                 a dark one to a  light one.  --PeterM
        \_ I have a light grey roof and no A/C. With a large shade tree on
           the south side of my house I never need A/C. However, won't
           this make my house colder in winter. It gets damn cold and I
           run the heater constantly. Not sure it's a net win.
           \_ Actually, I think it might help even in the winter.  A light roof
              means you gain less heat from the sun, but you also radiate less
              heat away.  Even in California, the net heat flow through your
              roof in winter is probably outward.
              \_ Check your physics crystal ball again.  Color does not effect
                 transmission, only absorbtion. -mrauser
                 \_ Sorry, he's more correct than you are.  Color, or more properly
                    material properties, can modify
                    both transmission AND absorbtion.  Some, but not all,
                    white materials have low emissivity as well as high
                    reflectivity.  Some DO have high emissivity and will
                    radiate heat well.
                 \_ What is "transmission" in thermal radiation?  I know
                    absorbtion is "going in" and emission is "going out".
                    -- !PP
                \_ Why do you think it is called "black body" radiation?
                   Black is the most emittive as well as the most absorptive.
           \_ Where do you live?  Most Bay Area locations don't ever need A/C,
              and barely need heat.  But A/C is more energy expensive than
              heating AND it probably has more of an effect on hot days
              than on cold days.
              \_ Yeah, I was thinking that I need to heat my house, not cool
                 it. But it would still help with global warming to paint
                 my roof white.
        \- The computation was done on an ultra 80.
           \_ What?
2009/5/27-6/3 [Uncategorized] UID:53049 Activity:nil
5/27    Why is the 10 year note taking a dump while the market is dumping?
        Isn't it supposed to be the reverse?
        \_ The market is worried that it might become tough to borrow money,
           which would be bad for the economy.
2009/5/27 [Politics/Foreign/Europe] UID:53050 Activity:nil
5/27    Tell us again how that inflexible European model causes unemployment:
2009/5/27-6/3 [Academia/Berkeley/CSUA/Troll/Aspolito] UID:53051 Activity:nil
5/27  aspo I found you on youtube
        \_ What, like you've never sahved your crotch...
           \_ I tried shaving my crotch once.  The shaving part was fine.  But
              when the hair started growing back, it was itchy as hell because
              the short hair rubbed against the skin.  -- !OP
              \_ That's part of the fun.
Berkeley CSUA MOTD:2009:May:27 Wednesday <Tuesday, Thursday>