After he saw the disastrous environmental effects of colonial plantations—cash crops, monoculture, irrigation, and deforestation—in Venezuela in 1800, Humboldt became the first scientist to talk about harmful human-induced climate change. Deforestation made the land barren, he said, and with the disappearance of brushwood, torrential rains washed away the soils, while water levels of lakes were falling. Humboldt was the first to explain the forest’s ability to enrich the atmosphere with moisture and its cooling effect, as well as its importance for water retention and protection against soil erosion.
At the Rio Apure in Venezuela, Humboldt commented on the devastation caused by the Spanish who had tried to control the annual flooding by building a dam. To make matters worse, they had also felled the trees that had held the riverbanks together like “a very tight wall,” with the result that the raging river carried more land away each year. At the Venezuelan coast, Humboldt noted how extensive pearl fishing had completely depleted oyster stocks. He warned that humans were meddling with the environment and that this could have an unforeseeable impact on “future generations.” It was all an ecological chain reaction.
“Everything,” Humboldt later said, “is interaction and reciprocal.” Towards the end of his life, he even prophetically warned about deleterious gas emissions at industrial centers. There were moments when he was so pessimistic that he painted a bleak future of voyages into space, when humans would spread their lethal mix of vice and greed even across other planets.
All this makes Humboldt the forgotten father of environmentalism and it’s time to remember him again. In a time when scientists are trying to understand and predict the global consequences of climate change, Humboldt’s interdisciplinary approach to science and nature is more relevant than ever. He refused to be tied to one discipline and insisted that all and everything was linked—humans, land clearing, plants, oceans, geography, atmospheric changes, temperature, and so on. Humboldt’s nature was a global force.
Even Humboldt’s historic data is still important today. In September, a group of scientists published an article in Proceedings of the National Academy of Sciences which analyzes the effects of climate change on alpine vegetation. They used observations that Humboldt collected on Chimborazo, a volcano in Ecuador, in June 1802. Retracing Humboldt’s ascent of the volcano, they proved that during the past 210 years, the plants have moved upwards by an average of 500 meters, in tandem with glacier retreat and increased temperatures. Chimborazo (then believed to be the highest mountain in the world) had been elemental to Humboldt’s vision of nature—it was here that his concept of nature as one of global patterns clarified.
Humboldt was a prescient proto–environmentalist and should be restored in the pantheon of nature. He was, after all, as one contemporary said, “the greatest man since the Deluge.”