Algae bloom spread due to heat absorption from the sun

Algae blooms spread and intensify due to increased heat absorption from the sun, especially during summer and as a result of climate change. Warmer temperatures and higher solar radiation directly affect water bodies in several ways:

• : Sunlight heats the surface layer of water, raising its temperature. Algae, particularly cyanobacteria, thrive in warm conditions, which accelerates their growth and reproduction256.

• : The sun’s heat causes the upper water layer to become significantly warmer than deeper layers, creating a thermocline (a sharp temperature gradient). This stratification limits mixing between layers, trapping nutrients and algae near the surface where sunlight is most abundant, further promoting blooms5.

• : Algae depend on sunlight for photosynthesis. Longer days and more intense sunlight in summer provide optimal energy for rapid algal proliferation25.

• : With increased temperatures and sunlight, nutrient cycling can change. Runoff from agriculture and urban areas often brings more nitrogen and phosphorus into water bodies during warm months, fueling additional algal growth268.

Climate change is amplifying these effects by causing more frequent and intense heatwaves, leading to longer and more severe algal bloom seasons369. The combination of heat, sunlight, and nutrient input creates ideal conditions for algal blooms to spread and persist.

In summary, the absorption of heat from the sun raises water temperatures and, together with abundant sunlight, creates favorable conditions for algae blooms to spread and intensify, especially when nutrients are also abundant256.

1. https://www.niehs.nih.gov/health/topics/agents/algal-blooms
2. https://www.moleaer.com/blog/lakes-ponds/why-do-algae-blooms-get-worse-in-summer
3. https://www.bbc.com/future/article/20230110-the-pollution-causing-harmful-algal-blooms
4. https://www.epa.gov/nutrientpollution/effects-dead-zones-and-harmful-algal-blooms
5. https://news.cuanschutz.edu/dbmi/summer-heat-gives-rise-to-algal-blooms-and-health-concerns
6. https://www.earthday.org/how-toxic-algae-blooms-work/
7. https://en.wikipedia.org/wiki/Algal_bloom
8. https://ocean.org/blog/algal-blooms-a-crisis-in-our-waters/
9. https://www.sciencedirect.com/science/article/pii/S1568988319300344