A government report on climate change released Friday said global warming is contributing to extreme weather in the United States. Outside scientists and officials from 13 federal agencies wrote the report, which is mandated by law every four years. This year’s analysis said extreme weather events “have already become more frequent, intense, widespread or of long duration.” The report warned that the negative effects of climate change could cost the U.S. economy hundreds of billions of dollars.

This month marks a full year that the noxious red tide, a harmful algae bloom that can kill fish and cause respiratory irritation in humans, has plagued the Florida coast. These algae blooms are nothing new for Florida, but the long duration of this one has some environmentalists pinning the blame on global warming and other human activities.

California lawmakers voted this summer for strict energy legislation that would require the state’s electricity sources to be 100 percent carbon-free within less than 30 years. The bill, passed by the State Senate and Assembly and signed by Gov. Jerry Brown on Sept. 10, will bump up California’s current mandate, increasing from 50 percent to 60 percent the amount of renewable power generation required in the state by 2030. The ultimate goal: All California electricity would be produced without greenhouse gases by 2045.

The Trump administration proposed new rules Tuesday that would roll back Obama-era constraints on coal-fired power plants. The Environmental Protection Agency would direct states to focus on making coal power plants more efficient and allow them to develop their own emissions reduction plans with federal oversight. Critics say the rules would allow utilities to run older, dirtier power plants more often and extend the plants’ overall operating life, undercutting potential environmental benefits. President Barack Obama aimed to cut U.S.

Agroecology, a back-to-nature farming approach based on ecological science, is growing into a movement proponents hope will transform the way we grow food. “Farming the land as if nature doesn’t matter has been the model for much of the Western world’s food production system,” wrote agroecology advocates Daniel Moss and Mark Bittman in The New York Times recently. “The results haven’t been pretty: depleted soil, chemically fouled waters, … a worsening of public health and more.”

Autonomous farming robots that target weeds directly are poised to disrupt the current practice of mass spraying of herbicides.

Swiss company ecoRobotix is one of several newcomers in the emerging field of digital agriculture. Its solar-powered robot, which looks something like a pingpong table on wheels, can identify and spray weeds for 12 hours straight without an operator. Its developers believe it will use 20 times less herbicide than traditional methods that involve spraying entire fields.

Hawaii’s Kilauea volcano erupted from its summit early Thursday, shooting a plume of ash about 30,000 feet into the sky. The explosion happened at about 6 a.m. HST after two weeks of volcanic activity. More than a dozen fissures east of the crater already spewed lava into neighborhoods, destroying at least 26 homes and 10 other structures. Hawaii Volcanoes National Park closed May 11 in anticipation of a possible eruption, and officials said they didn’t expect the explosion to be deadly as long as people stayed out of the park.