delta

Posted by Ellen

In the fall of 1898, these men were hard at work in a cotton gin in Bolivar County in north Mississippi.

1898 was a depression year; cotton was selling for barely 5 cents a pound. Out in the fields, the wages for cotton pickers had dropped from the going rate in the early 1890s of about 50 cents per  hundred pounds, which was what an average adult could pick in a day, down to 42 cents.

But most cotton in those years was grown not by wage laborers but by tenant farmers or sharecroppers. Tenants paid plantation owners about 2 bales of cotton (1,000 pounds) each year for a 40-acre plot; sharecroppers split the crop with the landowner, 50-50 or 25-75, depending on who provided the mule and who provisioned the family till the crop came in.

This lazy researcher was not readily able to learn how much the gin workers were paid, but we can be sadly certain that it was not much.

Posted by Ellen

The satellite view of Philadelphia in infrared, from a few days ago, led some people to ask for more false-color imagery of our planet. Here we've got a river delta in the tundra of eastern Siberia, where the River Lena empties into the Arctic Ocean. The image is from mid-summer, when the plants of the tundra were bursting with new growth, thanks to twenty-four hours a day of sunlight. The color scheme here is different from that of the Philadelphia scene but still not closely related to the colors a human eye would detect. The data displayed comes from three sensors on the Landsat satellite: one that detects infrared energy, another that detects near-infrared energy, which is very sensitive to the chemicals associated with growing vegetation, and a third sensor that picks up a part of the visible spectrum. Vegetation is green, exposed rock or soil is pink, wet soil (mud) is purple, and ice is blue.

Even in mid-summer, the sea ice floats close to shore. It will take another month or two for most of the ice to melt and/or wash out to sea, but as soon as it does freezing temperatures will return and ice formation will begin again.

The innumerable ponds and distributary streams are typical of flat places throughout the Arctic tundra, where permafrost just below the surface impairs drainage. Meltwater and rainwater sit on top of the permafrost all summer long, breeding mosquitoes...... which don't show up in the satellite imagery.