Brian Brettschneider says that the last few years have brought not only major events such as record-low sea ice in the Bering Sea and unprecedented Arctic wildfires, but also changes that are perhaps less stark, such as shifting tree lines, glacial melt, and changing vegetation.

Decades of data collected at the nation’s experimental forests show that the winters are getting shorter and warmer, meaning that there will be less snow to protect the microfauna and microflora below. To find out what this could mean for New England’s forests, biologist Pamela Templer of Boston University and her team have been conducting experiments to see what climate change has in store for the future of the forest floor.

Only two-thirds of Americans are confident in the knowledge that global warming is happening, and a bare majority understand that it’s mostly caused by human activities. One-third of Americans continue to believe that global warming is mostly natural. In reality, the scientific evidence demonstrating that global warming is happening and human-caused is overwhelming, which is why there is a 90 to 100 percent expert consensus on human-caused global warming.

Climate change has already wrought economic and physical havoc on US military bases. In Hampton Roads, an area of Virginia described by some as the greatest concentration of military might in the world, rising sea levels and worsening storms threaten basic operations. Elsewhere wildfires and melting permafrost limit the types of operations the military can conduct, affecting its ability to respond to conflicts and humanitarian disasters. While the military has commissioned studies and funded resilience efforts, climate change impacts continue to grow more serious and more difficult to address.

The kind of advances in spaceflight envisioned in the mid-twentieth century have largely failed to materialize, thereby limiting space exploration to relatively small areas of a very large galaxy. That will change with the advent of directed energy technologies, specifically laser propulsion. The privately funded Breakthrough Starshot program is already working on such a propulsion system to carry nanosatellite Star Chips to the nearest star system, Alpha Centauri. But powerful lasers—a dual-use technology much like rocketry, nuclear energy, and cyber technology, which have both security-related and civilian uses—have been largely stigmatized as weapons.