Marcus Webb 
What is a neural network? Strip away the brain metaphor and it is a stack of layers doing arithmetic, where each layer passes numbers to the next, and every connection has a weight that gets adjusted during training. That is genuinely the whole idea. The name is a loose analogy to neurons, not a description … Read more
How do clouds form? Warm air holds water vapor; cool it enough and it cannot hold it all, so the excess condenses into visible droplets. But there is a catch that makes the whole thing work: vapor will not condense into nothing. It needs a surface — a speck of dust, salt, smoke, or pollen … Read more
What is the water cycle? It is the continuous movement of water between the ocean, the atmosphere, the land, and back — driven by solar energy and gravity, with no beginning and no end. The total amount of water on Earth has been essentially fixed for billions of years. What changes is where it is … Read more
What causes global warming? An energy imbalance. Greenhouse gases in the atmosphere are transparent to incoming sunlight but absorb outgoing infrared radiation, so heat that should escape to space is retained. Add more of those gases and the planet warms until it radiates enough to rebalance. That is the entire mechanism, and it has been … Read more
How do ocean currents work? There are really two separate systems that happen to connect. Surface currents are pushed by wind. Deep currents are driven by density differences — cold, salty water sinking and spreading. Together they move an astonishing amount of heat around the planet, and they are a large part of why coastal … Read more
Why is the ocean salty? Because water flows toward the ocean carrying dissolved minerals, and the only way out is evaporation — which leaves the minerals behind. Over hundreds of millions of years, that one-way process has concentrated a great deal of salt. Rivers, by contrast, are constantly refreshed by rain and snow, so they … Read more
What is a volcano? Structurally it is just an opening in a planet’s crust where molten rock, gas, and ash reach the surface. But the interesting question is why rock melts down there in the first place — because under most conditions, the mantle is solid. Why Rock Melts Underground There are three ways to … Read more
What causes earthquakes? The short version: rock on either side of a fault wants to move, friction holds it in place, stress builds for decades or centuries, and then friction loses. The rock snaps to a new position in seconds and the stored elastic energy radiates outward as seismic waves. That is the shaking. The … Read more
What is pollination? It is the transfer of pollen — containing the male gametes — from the male part of a flower to the female part, so fertilization can happen. Plants cannot walk over and introduce themselves, so they outsourced. Roughly 75% of the world’s food crops depend to some degree on animal pollinators. The … Read more
What is bioluminescence? It is light produced by a chemical reaction inside a living organism — no heat, no electricity, no absorbed sunlight. It is genuinely “cold light,” and it is far more common than most people realize: the majority of deep-sea animals make it, and it evolved independently dozens of separate times. The Basic … Read more