plankton is ubiquitous, and their highest potential is during summer season. When the daylight is longer. Plankton has chlorophyll that attracts light, and summer shines at 80 degrees Fahrenheit which naturally clean water and forest from harmful bacteria & viruses, thus Forest stay green.
North Hemisphere greatly appreciate the summertime, light brings lot of food, rivers in the north ice cap defrosting and fishing season begins for bears and eagles.

Rivers. There are many rivers in North Hemisphere Arctic region, and largest forest. However, temperature has to be balanced in order to avoid flooding from melting glaciers. This region needs forest protection/ maintenance and river protection, because 2026 predicted an El Niño that may extend through autumn. North Hemisphere biggest challenge is melting glaciers, moreover, there are many glaciers mountain. Wild fires season in the North Hemisphere.

Note: during El Niño, sea level rise, causing rivers to flood during monsoon. La Niña oppsite, sea level decreases, less sunlight, extended winter.