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Some experts are concerned climate change will drive massive migrations as people are displaced from their homes, and it may already be happening. In a study published today in Science, researchers try to quantify how many people move from where to where under what conditions. They looked at asylum applications into the European Union and the weather in people's country of origin and found that as temperatures rose there, so did the number of people seeking asylum.
The context: It's timely — the U.S. Department of Defense has called climate change a "threat multiplier" and the defense authorization bill signed by President Trump last week acknowledges climate change as a "direct threat to the national security of the United States." Yet that view is noticeably absent from the president's National Security Strategy unveiled earlier this week.
What they found: At an average growing season temperature of about 68° Fahrenheit, which is the optimum one for agriculture, the number of applications for asylum was lowest. As the average temperature rose, so did the number of people from Somalia, Bangladesh and other warmer climate countries seeking asylum. But when cooler countries — such as Serbia — got warmer, fewer applications were received.
Erin Ross writes: In the beginning, Mars was a water world. But at some point in the planet's distant past, much of that water disappeared, leaving behind polar ice caps and a complex geology. Figuring out just where it went has been a major priority for scientists — life as we know it can't exist without water, and any future settlers would need a steady supply.
What's new: A new study, published Wednesday in Nature, suggests that much of what remains might be inaccessible. Some went into space, but even more of it may have sunk into the ground like a sponge, only to become bound up in minerals deep within the planet. "Mars, by virtue of its chemistry, was doomed from the start," study author Jon Wade, of Oxford University, tells Axios.
The earliest naturalists set out to document all of Earth's species. For five centuries, the plants of North and South America were plucked, dried and catalogued in the name of religion, medicine and science. Explorers and botanists amassed more than 22 million specimens that are housed in herbaria around the world. This includes the round-leaf cassia seen above that was collected in Brazil during Captain James Cook's first voyage to the New World in the 1760s.
Today researchers published a list of all known native vascular plants — the ferns, conifers and flowering plants we tend to notice — of the Americas. The stats:
The hope is that conservationists will use the database to manage a country's or region's plant assets, says Missouri Botanical Garden's Carmen Ulloa, who led the effort across multiple herbaria. "Now we know what we can conserve."