Editor’s note: From “climate adaptation” to “ecosystem services,” environmental jargon is everywhere these days. Conservation International’s blog looks to make sense of it in an occasional explainer series we’re calling “What on Earth?” In this installment and video , we break down “blue carbon,” a term you may not have heard of but which has immense importance for curbing climate change. What is ‘blue carbon’? “ Blue carbon ” is the carbon that is stored naturally by marine and coastal ecosystems, hence the name. Three types of coastal ecosystems — mangroves, seagrasses and tidal marshes — store half the “blue” carbon buried beneath the ocean floor. What’s so important about blue carbon? It’s important because the release of carbon into the atmosphere is a major driver of climate change , and because blue carbon ecosystems hold a LOT of carbon — in a single square mile, mangroves hold as much carbon as the annual emissions of 90,000 cars. That’s a lot. How is that even possible?…