In a remote stretch of the Amazon rainforest, a skinny steel tower will soon rise over 1,000 feet into the sky—higher than the Eiffel Tower, way higher than the trees. The Amazon Tall Tower Observatory is a joint effort by Brazil and Germany to figure out exactly how carbon dioxide fluctuates inside the South American rainforest, one of the "green lungs" of the planet. In recent decades, the proportion of carbon dioxide in the Earth's atmosphere as a whole has increased dramatically. Plants, however, need carbon dioxide to grow, and the dense vegetation of the Amazon rainforest has vast quantities of CO2 locked up inside it. The tower will help scientists measure how much carbon dioxide the rainforest absorbs year by year—or how much it releases. Scientists aren't entirely sure, hence the need for this tower. To that end, the structure will be replete with high-tech instruments monitoring air chemistry. But why does it need to be so ridiculously tall? While shorter towers can measure how a local patch of rainforest breathes, this 1,000-foot tower will reach far past the trees, giving an overview of the entire eastern Amazon. via Gizmodo.