If the Appalachians are ancient, rounded, and quiet — worn down by hundreds of millions of years — then what are the Rockies? The answer is: still under construction. This episode picks up where the eastern geography series left off, and heads west into some of the most dramatic, geologically active, and ecologically distinct landscapes on the continent. Young Mountains and the Rain Shadow That Made the West The Rocky Mountains are young by geological standards — sharp, dramatic, still rising. Unlike the Appalachians, they haven’t been worn down yet. The Cascades and Sierra Nevadas do something remarkable to the weather: they intercept the moist Pacific air as it moves inland, force it upward, cool it, and squeeze out enormous amounts of rain on the western slopes. By the time the air crosses the mountain crest and descends on the eastern side, the moisture is gone. The land on the far side sits in what’s called a rain shadow — which is why the western slope of the Cascades is one of the wettest places in North America while Oregon’s east side and the Great Basin are semi-arid desert. Same latitude, completely different worlds. The Great Basin: Where Rivers Go to Disappear Between the Rockies and the Sierra Nevadas lies one of the continent’s most unusual landscapes: the Great Basin. Rivers here have no outlet to the ocean. They flow inward toward salt lakes and desert playas and simply evaporate. The Great Salt Lake is the largest remnant of an ancient inland sea called Lake Bonneville, which once covered much of the region. The ecology is highly specialized — sagebrush, juniper, pronghorn antelope (the fastest land animal in North America) — and it all exists because the mountains blocked the rain entirely. The Pacific Coast: Cold, Productive, and Geologically Volatile The Pacific Ocean is older, colder, and geologically more violent than the Atlantic. The western coast of North America sits on the Ring of Fire. The Juan de Fuca plate pushes under the North American plate, building the Cascades and threatening a mega-earthquake along the Pacific Northwest coast. The California Current flows southward, bringing cold water from the north and driving upwelling from the deep ocean that produces some of the richest marine life on Earth — kelp forests, fish populations, seabird colonies, sea otters, gray whales, humpback whales. The Pacific Flyway runs this entire coastline from Alaska to Mexico, carrying shorebirds, waterfowl, raptors, and songbirds in enormous numbers every spring and fall. Temperate Rainforests, the Gulf of Mexico, and the Longleaf Pine Where Pacific moisture hits the mountains directly, you get the temperate rainforests of the Pacific Northwest — the Olympic Peninsula, the western slopes of the Cascades — 140 inches of rain in some locations, trees of staggering size and age. Jill’s Olympic Peninsula road trip is one of her all-time favorite travel memories. Moving south and east, the episode fills in the missing pieces: the Gulf Coastal Plain (ancient seafloor, karst landscape, cypress swamps, bayous), the once-vast Longleaf Pine Savannah (now reduced to less than 3% of its original 90 million acres), and the Gulf of Mexico itself — not a warm-water backdrop but the engine that drives the entire continent’s weather and a critical corridor for the most dramatic bird migration event in North America: the trans-Gulf crossing. Alaska, the Boreal Forest, and How It All Connects Alaska is its own category — larger than Texas, California, and Montana combined, with more coastline than the entire lower 48. It holds tundra, boreal forest, temperate rainforest, glaciers, active volcanoes, and some of the most productive marine environments on Earth. And the boreal forest — the taiga — stretching across Canada, Russia, Scandinavia, and Siberia, is the breeding ground for nearly 3 billion birds, more than half the species that migrate through North America. That yellow-rumped warbler in your backyard in September? There’s a reasonable chance it hatched in a spruce bog in northern Canada. North America is not a collection of separate places. The birds connect them. The rivers connect them. The weather connects them. Jill’s Links http://jillfromthenorthwoods.com https://www.buymeacoffee.com/smallstepspod Twitter - https://twitter.com/schmern YouTube @BuzzBlossomSqueak By choosing to watch this video or listen to this podcast, you acknowledge that you are doing so of your own free will. The content shared here reflects personal experiences and opinions and is intended for informational and educational purposes only. I am not a licensed biologist, ecologist, or wildlife professional. Any nature observations, identifications, or suggestions offered should not be considered a substitute for professional scientific or environmental guidance. Always follow local regulations when observing or interacting with wildlife and natural spaces. You are solely responsible for any decisions or actions you take based on this content.
