Estuarine water clarity depends on the concentrations of aquatic constituents, such as colored dissolved organic matter, phytoplankton, inorganic suspended solids, and detritus, which are influenced by variations in riverine inputs. These constituents directly affect temperature because when water is opaque, sunlight heats a shallower layer of the water compared to when it is clear. Despite the importance of accurately predicting temperature variability, many numerical modeling studies do not adequately account for this key process. In this study, we quantify the effect of water clarity on heating by comparing two simulations of a hydrodynamic-biogeochemical model of the Chesapeake Bay for the years 2001–2005, in which (1) water clarity is constant in space and time for the computation of solar heating, compared to (2) a simulation where water clarity varies with modeled concentrations of light-attenuating materials. In the variable water clarity simulation, the water is more opaque, particularly in the northern region of the Bay. This decrease in water clarity reduces the total heat, phytoplankton, and nitrate throughout the Bay. During the spring and summer months, surface temperatures in the northern Bay are warmer by 0.1 °C and bottom temperatures are colder by 0.2 °C in the variable light attenuation simulation. Warmer surface temperatures encourage phytoplankton growth and nutrient uptake near the head of the Bay, and fewer nutrients are transported downstream. These impacts are greater during higher river flow years, when differences in temperature, nutrients, phytoplankton, and zooplankton extend further seaward compared to other years. This study demonstrates the consequences of utilizing different light calculations for estuarine heating and biogeochemistry.

河口水的清晰度取决于河流成分输入的变化而影响的水生成分的浓度，例如有色溶解的有机物，浮游植物，无机悬浮固体和碎屑。这些成分直接影响温度，因为与不透明的水相比，当水不透明时，阳光会加热浅层的水。尽管准确预测温度变化的重要性，但许多数值模型研究并未充分说明这一关键过程。在这项研究中，我们通过比较切萨皮克湾2001-2005年的水动力-生物地球化学模型的两个模拟来量化净水对加热的影响，其中（1）净水在空间和时间上是不变的，用于计算太阳能供热 与（2）相比，水的清晰度随模拟的光衰减材料浓度而变化。在可变净度模拟中，水更加不透明，尤其是在海湾北部地区。水透明度的下降会降低整个海湾的总热量，浮游植物和硝酸盐。在春季和夏季，在可变光衰减模拟中，北部海湾的地表温度升高了0.1°C，底部温度降低了0.2°C。温暖的地表温度促进了浮游植物的生长和湾头附近的养分吸收，而更少的养分向下游输送。与其他年份相比，在较高的河流流量年份，温度，养分，浮游植物和浮游动物之间的差异进一步向海延伸时，这些影响更大。