Wednesday, April 12, 2017
Drying out?
Is the period of super-rain over? Feels like it, but numbers tell the story. Here's a quickie chart of precip in March, plus the first 11 days of April.
You can definitely see a mode shift. April is behaving more like normal spring, with occasional rain mostly less than 1/4 inch.
So far it's not making a lot of difference because the soil is still oversaturated. October was super-wet, then Nov was super-cold, creating permafrost. A week ago the thaw finally reached the level of water pipes, resulting in some flooding at houses that were vacant during the winter. Vacant house = no flow = total freeze.
How long will it take for the soil to dry out? No way of knowing. Grass and trees will help to suck out the upper layer.
However! In this case the numbers disagree with 'feels-like'. Using a USGS soil-moisture website, this map shows moisture at several depths. It looks like the curves went beyond measuring limits in March, but April is returning to roughly the same as April of last year.
Now the soil temperature. Used a two-year span to see more of the pattern.
Here's the real diff. Deeper soil (green curve) froze sooner and stayed frozen a lot longer than usual, suddenly thawing in late March. This matches the observed results in terms of pipe breaks and landslides.
You can definitely see a mode shift. April is behaving more like normal spring, with occasional rain mostly less than 1/4 inch.
So far it's not making a lot of difference because the soil is still oversaturated. October was super-wet, then Nov was super-cold, creating permafrost. A week ago the thaw finally reached the level of water pipes, resulting in some flooding at houses that were vacant during the winter. Vacant house = no flow = total freeze.
How long will it take for the soil to dry out? No way of knowing. Grass and trees will help to suck out the upper layer.
However! In this case the numbers disagree with 'feels-like'. Using a USGS soil-moisture website, this map shows moisture at several depths. It looks like the curves went beyond measuring limits in March, but April is returning to roughly the same as April of last year.
Now the soil temperature. Used a two-year span to see more of the pattern.
Here's the real diff. Deeper soil (green curve) froze sooner and stayed frozen a lot longer than usual, suddenly thawing in late March. This matches the observed results in terms of pipe breaks and landslides.Labels: Heimatkunde
¶ 2:46 AM
