Sunlight

Although I spent years flying from San Francisco to Seattle, it wasn't until I started flying from Portland to San Francisco that the differences in the quality of the sunlight crept into my consciousness.  San Francisco is always bright and sunny, but it's a thin bright--almost like a very sheer white film filters the light.  This compared to the Northwest's richer light, that may not be as brilliant, but makes colors intense and truer.  I'm sure its probably due to atmospheric differences.  And it might also be the relative population and surfaces reflecting the sun in the Bay Area versus so much shadow and green absorbing the sun in Washington and Oregon.  Of course days and seasons make it variable, but it's a sense of the overall density of light that I get.

My old house, Palo Alto, California

My best explanation is likening it to the 'saturation' adjustment in photo apps.  The skies in San Francisco are generally a paler, thinner blue, over-exposed; where Seattle and Portland skies have more depth of color and vibrance.  

My new house, West Linn, Oregon

Paris is more like San Francisco.  

But once you get south in France, the light changes.  Provence is suffused with a thick, rich sunlight.  There's gold in the light, a density of color, an intense blue sky.  The air feels almost tangible, the buildings and foliage soak up the light--rather than reflect it.

And with these differences in sunlight, the impression, atmosphere and 'feel' of places differs.  Of course there is the actual warmth of locations due to the relative distance to the equator.  But even a cool sunlight in Provence radiates from the landscape and envelopes you.  

It's easy to understand why 'Impressionism' was born in France--where the sun saturates and drenches the landscapes.  Impressionists focused on everyday subjects and plein air (outdoors) scenes.  They captured changes in the quality of light with bold brush strokes of concentrated, intense color.  Some artists even conveyed the shimmer and movement of heat. 

Claude Monet, France 1840-1926

'Post-Impressionism' extended Impressionism, but with even more freedom and movement in the paintings.  While they continued using vibrant colors and painting from life, they tended toward the abstract and symbolic, often distorting form for expressive effect.

Vincent Van Gogh - Dutch, painted much of his work in France, 1853-1890

Many Impressionists captured the warm, rich light and the mood, that makes Provence such a magical place.