Re: Why does the sun seem brighter in the morning than it does in the afternoon

There are a few things that affect how bright the sun looks to us.  One 
of these is the amount of air the sun passes through, and another is what 
is in the air.

In general, sunlight has to pass through more air in the early morning 
and the late afternoon.  That's because, when the sun is high in the sky, 
it is shining straight down on us, and it only has to pass through about 
60 miles of atmosphere to reach the earth's surface.  On the other hand, 
when the sun is near the horizon, it's passing through twice as much air, 
and this absorbs more sunlight, making the sun somewhat less bright.  
However, this dimming effect drops off rapidly as the sun rises so that, 
even just an hour or so after sunrise, it is not very significant.

The other effect is somewhat more interesting.  Dust, water vapor, air 
pollution, and all the other stuff in the atmosphere tends to scatter and 
absorb sunlight.  When there is more junk in the air, the sun looks 
dimmer.  In the evening, this also makes the sun look redder, but you 
don't notice this as much during the day.

In the morning, the air is fairly clean, so there is less dust to dim and 
scatter sunlight.  As the day goes no, the ground warms up, winds get 
somewhat stronger, and more dust is raised into the air.  This is one 
reason why we have more thunderstorms in the afternoon than in the early 
morning or at night - the thermal energy from the sun helps to drive the 
weather that causes thunderstorms.

It may also be that, in the morning, the sun is closer to dark things 
like trees, mountains, or buildings.  When you look at the sun, you will 
tend to "compare" its brightness to what it is near; if it's close to a 
number of things that are dark, it will look brighter in comparison.  At 
noon, with the sun high in the sky, it's not close to those dark things, 
so it won't as bright by comparison.

So, when we put this all together, we could expect that, in the morning, 
we are looking at the sun through a little bit thicker chunk of 
atmosphere, which will tend to make it a little dimmer than in later in 
the day.  On the other hand, the atmosphere is much dirtier in the 
afternoon, and the extra stuff in the air will tend to make the sun a 
little dimmer; in your location, it seems that the second effect is more 
important than the first, which is why you would see the sun to be 
brighter in the morning.

Having said all of this, you also need to make sure you don't look 
straight at the sun!  No matter where it is in the sky, it's very bright, 
and looking directly at it is a good way to damage your vision.  In the 
days of sailing ships, many ship's captains were blind in one eye because 
they would use a sextant to determine their position by seeing how far 
above the horizon the sun was at noon-time.  I even read in one book that 
this is why so many sailors (including pirates) wore eye-patches.  So be 
careful!