12 June 2020

Using dynamic modeling to reduce acidification

Options Summer 2020: According to IIASA research, appropriate indicators are needed to characterize the sensitivity of ecosystems and help inform effects-based emission reduction policies to ensure surface water recovery from acidification by 2050.

© Pawellfilms | Dreamstime

© Pawellfilms | Dreamstime

Most countries around the globe are looking for effective
ways to reduce nitrogen and sulphur emissions. Over the last two decades, researchers have utilized the concept of critical loads to analyze air pollution inputs to model corrective protocols in Europe.

More recently, researchers developed the concept of target loads, which is an extension of the critical loads concept that allows researchers to define depositions of nitrogen and sulphur, as well as the target year for when chemical limits will no longer be violated.

In a study by IIASA Air Pollution and Greenhouse Gases researcher Maximilian Posch and colleagues, the authors used target loads to model acidic deposition in 848 lakes across Finland, Norway, Sweden, and the UK. They found that in the majority of these lakes, the critical limit would be achieved by 2050.

However, current protocols would not ensure that nearly a quarter of these lakes recover from acidification over the next three decades. Additionally, the results show that target loads can be used effectively on a large, regional scale, and can inform effects-based emission reduction policies.

“Much has been done over the last three decades to reduce sulphur and nitrogen emissions in Europe and North America,” explains Posch. “Nevertheless, sensitive ecosystems still suffer from the deposition of nitrogen and sulphur. To help targeting and timing of further emission reductions, appropriate indicators are needed to characterize the sensitivity of ecosystems.”

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Last edited: 04 June 2020


Maximilian Posch

Guest Research Scholar Pollution Management Research Group - Energy, Climate, and Environment Program

T +43(0) 2236 807 440

Research program involved

Options Summer 2020

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Posch, M. , Aherne, J., Moldan, F., Evans, C.D., Forsius, M., Larssen, T., Helliwell, R., & Cosby, B. (2019). Dynamic Modeling and Target Loads of Sulfur and Nitrogen for Surface Waters in Finland, Norway, Sweden, and the United Kingdom. Environmental Science & Technology 53 (9), 5062-5070. 10.1021/acs.est.8b06356.

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