Daily Climate: All farming depends on the weather, but few foods are more dependent on a specific climate than maple syrup. After all, for the sugar maple’s sap to run at all requires cooperative weather — freezing nights followed by warmer days. But with the build-up of invisible greenhouse gases in the atmosphere, those temperature swings don’t happen as reliably. At risk is an American tradition that stretches back even before Europeans discovered the “New World.” “Weather controls it …