https://eos.org/research-spotlights/rising-temperatures-reduce-colorado-river-flow Source:   By Sarah Stanley, Eos/AGU. Excerpt: The Colorado River flows through seven U.S. states and northern Mexico. Along the way, it provides drinking water to millions of people and irrigates thousands of square kilometers of cropland. However, although annual precipitation in the region increased by about 1% in the past century, the volume of water flowing down the river has dropped by over 15%. While it’s true that so much of the water is diverted on its route to the Gulf of California that it no longer discharges into the ocean, scientists have recently found an additional cause in the reduction in river flow. New research by Xiao et al. examines the causes behind this 100-year decline in natural flow, teasing out the relative contributions of rising temperatures and changes in precipitation. ...Rising temperatures can lower flow by increasing the amount of water lost to evaporation from s...

https://www.sciencemag.org/news/2018/11/why-536-was-worst-year-be-alive Source:   By Ann Gibbons, Science Magazine. Excerpt: Ask medieval historian Michael McCormick what year was the worst to be alive, and he's got an answer: "536." Not 1349, when the Black Death wiped out half of Europe. Not 1918, when the flu killed 50 million to 100 million people, mostly young adults. But 536. ...A mysterious fog plunged Europe, the Middle East, and parts of Asia into darkness, day and night—for 18 months. "For the sun gave forth its light without brightness, like the moon, during the whole year," wrote Byzantine historian Procopius. Temperatures in the summer of 536 fell 1.5°C to 2.5°C, initiating the coldest decade in the past 2300 years. Snow fell that summer in China; crops failed; people starved. The Irish chronicles record "a failure of bread from the years 536–539." Then, in 541, bubonic plague struck the Roman port of Pelusium, in Egypt. What came to b...