Climate adjustment reads the chart's weather — winter charts crave fire's warmth, summer charts crave water's moisture.
Winter metal-water and midsummer fire-earth charts need adjustment most — one climate god there outweighs ten wealth stars. The idea comes from Qiong Tong Bao Jian: under the same moon, winter Jia begs for fire while summer Jia begs for water first. The engine uses it as one of three cross-checks.