In 1899 gold was discovered in the beaches along the shores of the Bering Sea in northwest Alaska. By 1900 over 10,000 people were panning and digging and sluicing for gold in the beach sand while living in a huge tent city that stretched for 30 miles along the coast. The gold rush city of Nome was being built just behind the gold-bearing beach sands, and by 1904 enough boards, nails, and alcohol had been shipped north to build dozens of saloons and brothels, along with a respectable number of churches, schools, and stores selling mining supplies and other goods. There was even a newspaper and a downtown district with electric lights.
By 1905 Nome was a thriving city, but the gold mining on the beach was starting to play out. What Nome needed to keep going was another beach filled with gold. But where they could they find another beach filled with gold?
Miners are resourceful people, and soon enough they found two new beaches, which they named "Second Beach" and "Third Beach." But Second Beach and Third Beach were not located along the shores of the Bering Sea---they were found miles inland from the current beach, and at elevations lying 10 m to 100 m higher then the current level of the the ocean.
In the century since the Nome gold rush, gold miners have traced and excavated almost all the beach sands of the Second Beach and Third Beach. They've exposed and mined not only beach sand occurring high above modern sea level, but also ancient sand spits and ancient deltas built into the ocean when it stood higher then it does today. Most recently huge gold dredges were brought to Nome to excavate these beach sands. I visited the last operating Gold Dredge in Nome about 10 years ago, and it was still excavating its way along a segment of Second Beach.
The discovery of Second Beach and Third Beach at Nome marks the first recognition that sea level had been much higher in the recent geologic past then it is today. Modern research indicates that Second Beach formed about 125,000 years ago, when sea level was about 7-12 m higher then it is today. Third Beach formed about 400,000 years ago, when sea level was even higher.
Sea levels are rising around the world today due to global warming. Unless Greenhouse gases like CO2 and CH4 are kept out of the atmosphere by global treaty or removed by geoengineering, Earth will continue to warm and sea level will continue to rise. How high will sea level rise? You can see for yourself by visiting Nome and walking along Second Beach, created 125,000 years ago when the Earth was just a bit warmer then it is today.
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