In September 1900, the growing island city of Galveston, Texas, was home to about 37,000 people. That was before the hurricane struck. What has come to be known as the 1900 Galveston Hurricane made landfall on Sept. 8 and tore through the city, leveling more than two-thirds of the buildings and killing at least 6,000 (and possibly as many as 12,000) people, making it the deadliest hurricane to strike in the United States.

Despite its terrible costs, the Galveston hurricane has an important legacy. It led to newer and better methods of predicting hurricanes, and it also inspired the creation of new ways of protecting people from these deadly storms.

To understand that legacy, however, we first need to go back to the decades before the storm. Galveston Island — a sand barrier island just 8.7 feet above sea level at its peak — was hit by several big storms in the 19th century. So was another coastal town, Indianola, which was wiped out by a storm in 1886. These storms led to multiple calls for beachfront storm walls to be built in Galveston.

Those calls were dismissed by Isaac Cline, the Galveston section director for the newly established U.S. Weather Bureau. In 1891 he wrote, "It would be impossible for any cyclone to create a storm wave which could materially injure the city."

Nine years later, that decision would cost both him and the city, as would inaction by Washington bureaucrats, who saw reports that a storm was forming to the southwest of Cuba but refused to acknowledge that it was worsening or that it was headed toward Texas. Cline said he wrote to Washington, predicting a heavy loss of life, but he was not allowed to declare a potential emergency. As a result of this inaction, no warning was issued and few people were evacuated to the mainland.

By the time the hurricane struck Galveston, its winds had increased to an estimated 145 miles per hour. Today that would make it a Category 4 storm, but those classifications did not exist at the time. The winds brought the waves, massive storm surges of more than 15 feet — several feet taller than the highest point on the island. In addition to destroying thousands of buildings, the water washed away bridges and telegraph lines, making it all-but-impossible to send for or receive help from the mainland.

In his account of that day, Cline recalled the horror as four-foot-tall waters surged into his home: "... the force of the waves acted as a battering ram against which it was impossible for any building to stand for any length of time, and at 8:30 p.m. my residence went down with about fifty persons who had sought it for safety, and all but eighteen were hurled into eternity. Among the lost was my wife, who never rose above the water after the wreck of the building. I was nearly drowned and became unconscious, but recovered through being crushed by timbers and found myself clinging to my youngest child, who had gone down with myself and wife. Mr. J. L. Cline [his brother] joined me five minutes later with my other two children, and with them and a woman and child we picked up from the raging waters, we drifted for three hours, landing 300 yards from where we started." (For more of Cline's accounts from both before and after the storm, as well as the science of Hurricanes, check out the book "Isaac's Storm: A Man, a Time, and the Deadliest Hurricane in History" by Erik Larson.)

Rebuilding homes, walls and lives

The storm changed Cline's opinion about sea walls. As he wrote two weeks after the storm, "I believe that a sea wall, which would have broken the swells, would have saved much loss of both life and property." Less than two years later, the first 17-foot sea walls were built around the island. Meanwhile, in what has been called "Galveston's finest hour," the city was rebuilt. Sand dredged to the island, raising its elevation by several yards. It all worked: by the time another hurricane struck Galveston in 1915, the island was almost completely protected. These lifesaving adaptations would soon be put to use by other cities.

As Galveston rebuilt, so did Cline. At first bereft by the death of his pregnant wife, he soon moved to New Orleans. There, at the mouth of the Mississippi River, he became a leading researcher into flooding and the nature of hurricanes and other tropical storms. He learned to forecast future storms and literally wrote the book (actually multiple books) on the subject, including 1942's "A Century of Progress in the Study of Cyclones: Aids in Forecasting Movements and Destructive Agencies in Tropical Cyclones."

The 1900 Galveston Hurricane was probably the first known example of what would today be called an extreme hurricane, or an X-storm. It was a terrible tragedy, but also an opportunity to learn. And more than a century later, it remains an example of what can happen when hubris and arrogance get in the way of human safety — and the consequences of the unstoppable storms we may see more of in the future.