Bridging global and basin scale water quality modeling towards enhancing global water quality modeling and management

European Geosciences Union General Assembly 2018 Vienna | Austria | 8-13 April 2018

European Geosciences Union General Assembly 2018 Vienna | Austria | 8-13 April 2018

Challenges to current global WQ modeling call for enhancements of global WQMs.

 Strong spatiotemporal variability of biogeochemical processes v.s. coarse resolution of global WQMs

 Interdependence of pollutant processes & env. effects v.s. uncoupled modeling of different pollutants

 Risks of complex global WQMs with insufficient data to drive and/or validate the models

Bridging global and basin scale water quality modeling towards enhancing global water quality modeling and management

Ting Tang ^1,* , Yoshihide Wada ^1,2,3 , Maryna Strokal ⁴ , Peter Burek ¹ , and Simon Langan ¹

1 International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria; ² Department of Physical Geography, Utrecht University, Utrecht, Netherlands;

3 NASA Goddard Institute for Space Studies, New York, USA; ⁴ Water Systems and Global Change group, Wageningen University & Research, Wageningen, Netherlands

 Basin/field scale water quality (WQ) models for a wide range of pollutants have been actively developed over the past few decades and widely used for a variety of purposes.

 Global water quality models (WQMs), such as Global-NEWS-2 ¹ , are increasingly used to gain unique insight into the state and trend of WQ issues under global climate and socio-economic changes.

 A scale‐independent WQM currently does not exist, but linking WQM of different spatial scales can help to address water quality issues across different scales.

 In this work, we argue that WQMs of different spatial scales should be better linked and support each other to ensure effective WQ management and further development of global WQMs.

 Two directions are proposed to improve the linkages of WQ modeling across different spatial scales:

 multiscale WQ modeling towards enhanced WQ and water resource management, and

 refinement and enhancement of global WQ models using smaller-scale mechanistic understanding.

Motivation

Example of dissolved inorganic nitrogen (DIN) transport into surface water

 Context-specific basin-scale WQ management benefits from global WQMs to identify regions of concerns and requires local implementation of mitigation and/or prevention measures.

 Such an integrated manner of management strategy requires close collaborations among modelers of different spatial scales.

Proposed framework to bridge WQMs of different spatial scales

Multiscale WQ modeling towards enhanced WQ management

Enhancement of global WQMs

References

1 Mayorga, E., Seitzinger, S. P., Harrison, J. A., Dumont, E., Beusen, A. H. W., Bouwman, A. F., … Van Drecht, G. (2010). Global Nutrient Export from WaterSheds 2 (NEWS 2): Model development and implementation. Environmental Modelling and Software, 25(7), 837–853.

2 Neitsch, S., Arnold, J., Kiniry, J., Williams, J.R. (2011). Soil and water assessment tool: theoretical documentation, version 2009. USDA-ARS Grassland, Soil and Water Research Service, Temple, TX.

3 Gassman, P., Williams, J., Wang, X., Saleh, A., Osei, E., Hauck, L. M., … Flowers, J. D. (2010). The Agricultural Policy Environmental Extender (APEX) model: An emerging tool for landscape and watershed environmental analyses. Transactions of the ASABE, 53(3), 711–740.

4 Abrahamsen, P., & Hansen, S. (2000). Daisy: an open soil-crop-atmosphere system model. Environmental Modelling & Software, 15(2000), 313–330.

5 Tang, T., (2012) Modeling on Pesticide Transport into Surface Water and its Ecotoxicological Risk Assessment for a Tile-drained River Basin. Msc Thesis, UNESCO-IHE Institute for Water Education.

6 Hoang, L., van Griensven, A., & Mynett, A. (2017). Enhancing the SWAT model for simulating denitrification in riparian zones at the river basin scale. Environmental Modelling & Software, 93, 163-179.

*Contact: tangt@iiasa.ac.at

Water Program, IIASA http://www.iiasa.ac.at/

Global Basin Field/Local

Identify global hotspots and source apportionment

Regional policy- making to address regions, basins &

pollution sources of concern

Assist in designing long-term basin management plans, considering

climate and socio-economic changes:

• Identify critical source area and critical transport pathways

• Project future changes and evaluate potential preventive strategies

Local actions in response to basin management plans

Legend g_basin '2000$'.c0DINyld

0 - 50 51 - 100 110 - 150 160 - 200 210 - 250 260 - 300 310 - 350 360 - 400 410 - 450 460 - 500 510 - 550 560 - 600 610 - 650 660 - 700 710 - 750 760 - 800 810 - 850 860 - 900 910 - 950 960 - 1,000 1,100 - 1,100 1,200 - 1,100 1,200 - 1,200 1,300 - 1,200 1,300 - 1,300 1,400 - 1,300 1,400 - 1,400 1,500 - 1,400 1,500 - 1,500 1,600 - 1,500 1,600 - 1,600 1,700 - 1,600 1,700 - 1,700 1,800 - 1,700 1,800 - 1,800 1,900 - 1,800 1,900 - 1,900 2,000 - 1,900 2,000 - 2,000 2,100 - 2,000 2,100 - 2,100 2,200 - 2,100 2,200 - 2,200 2,300 - 2,200 2,300 - 2,300 2,400 - 2,300 2,400 - 2,400 2,500 - 2,400 2,500 - 2,500 2,600 - 2,500 2,600 - 2,600 2,700 - 2,600 2,700 - 2,700 2,800 - 2,700 2,800 - 2,800 2,900 - 2,800 2,900 - 2,900 3,000 - 2,900 3,000 - 3,000 3,100 - 3,000 3,100 - 3,100 3,200 - 3,100 3,200 - 3,200 3,300 - 3,200 3,300 - 3,300 3,400 - 3,300 3,400 - 3,400 3,500 - 3,400 3,500 - 3,500 3,600 - 3,500 3,600 - 3,600 3,700 - 3,600 3,700 - 3,700 3,800 - 3,700 3,800 - 3,800 3,900 - 3,800 3,900 - 3,900 4,000 - 3,900 4,000 - 4,000 4,100 - 4,000 4,100 - 4,100 4,200 - 4,100 4,200 - 4,200 4,300 - 4,200 4,300 - 4,300 4,400 - 4,300 4,400 - 4,400 4,500 - 4,400 4,500 - 4,500 4,600 - 4,500 4,600 - 4,600 4,700 - 4,600 4,700 - 4,700 4,800 - 4,700 4,800 - 4,800 4,900 - 4,800 4,900 - 4,900 5,000 - 4,900 5,000 - 5,000 5,100 - 5,000 5,100 - 5,100 5,200 - 5,100 5,200 - 5,200 5,300 - 5,200 5,300 - 5,300 5,400 - 5,300 5,400 - 5,400 5,500 - 5,400 5,500 - 5,500 5,600 - 5,500 5,600 - 5,600 5,700 - 5,600 5,700 - 5,700 5,800 - 5,700 5,800 - 5,800 5,900 - 5,800 5,900 - 5,900 6,000 - 5,900 6,000 - 6,000 6,100 - 6,000 6,100 - 6,100 6,200 - 6,100 6,200 - 6,200 6,300 - 6,200 6,300 - 6,300 6,400 - 6,300 6,400 - 6,400 6,500 - 6,400 6,500 - 6,500 6,600 - 6,500 6,600 - 6,600 6,700 - 6,600 6,700 - 6,700 6,800 - 6,700 6,800 - 6,800 6,900 - 6,800 6,900 - 6,900 7,000 - 6,900 7,000 - 7,000 7,100 - 7,000 7,100 - 7,100 7,200 - 7,100 7,200 - 7,200 7,300 - 7,200 7,300 - 7,300 7,400 - 7,300 7,400 - 7,400 7,500 - 7,400 7,500 - 7,500 7,600 - 7,500 7,600 - 7,600 7,700 - 7,600 7,700 - 7,700 7,800 - 7,700 7,800 - 7,800 7,900 - 7,800 7,900 - 7,900 8,000 - 7,900 8,000 - 8,000 8,100 - 8,000 8,100 - 8,100 8,200 - 8,100 8,200 - 8,200 8,300 - 8,200 8,300 - 8,300 8,400 - 8,300 8,400 - 8,400 8,500 - 8,400 8,500 - 8,500 8,600 - 8,500 8,600 - 8,600 8,700 - 8,600 8,700 - 8,700 8,800 - 8,700 8,800 - 8,800 8,900 - 8,800 8,900 - 8,900 9,000 - 8,900 9,000 - 9,000 9,100 - 9,000 9,100 - 9,100 9,200 - 9,100 9,200 - 9,200 9,300 - 9,200 9,300 - 9,300 9,400 - 9,300 9,400 - 9,400 9,500 - 9,400 9,500 - 9,500 9,600 - 9,500 9,600 - 9,600 9,700 - 9,600 9,700 - 9,700 9,800 - 9,700 9,800 - 9,800 9,900 - 9,800 9,900 - 9,900 10,000 - 9,900 10,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 Legend

g_basin '2000$'.c0DINyld

0 - 50 51 - 100 110 - 150 160 - 200 210 - 250 260 - 300 310 - 350 360 - 400 410 - 450 460 - 500 510 - 550 560 - 600 610 - 650 660 - 700 710 - 750 760 - 800 810 - 850 860 - 900 910 - 950 960 - 1,000 1,100 - 1,100 1,200 - 1,100 1,200 - 1,200 1,300 - 1,200 1,300 - 1,300 1,400 - 1,300 1,400 - 1,400 1,500 - 1,400 1,500 - 1,500 1,600 - 1,500 1,600 - 1,600 1,700 - 1,600 1,700 - 1,700 1,800 - 1,700 1,800 - 1,800 1,900 - 1,800 1,900 - 1,900 2,000 - 1,900 2,000 - 2,000 2,100 - 2,000 2,100 - 2,100 2,200 - 2,100 2,200 - 2,200 2,300 - 2,200 2,300 - 2,300 2,400 - 2,300 2,400 - 2,400 2,500 - 2,400 2,500 - 2,500 2,600 - 2,500 2,600 - 2,600 2,700 - 2,600 2,700 - 2,700 2,800 - 2,700 2,800 - 2,800 2,900 - 2,800 2,900 - 2,900 3,000 - 2,900 3,000 - 3,000 3,100 - 3,000 3,100 - 3,100 3,200 - 3,100 3,200 - 3,200 3,300 - 3,200 3,300 - 3,300 3,400 - 3,300 3,400 - 3,400 3,500 - 3,400 3,500 - 3,500 3,600 - 3,500 3,600 - 3,600 3,700 - 3,600 3,700 - 3,700 3,800 - 3,700 3,800 - 3,800 3,900 - 3,800 3,900 - 3,900 4,000 - 3,900 4,000 - 4,000 4,100 - 4,000 4,100 - 4,100 4,200 - 4,100 4,200 - 4,200 4,300 - 4,200 4,300 - 4,300 4,400 - 4,300 4,400 - 4,400 4,500 - 4,400 4,500 - 4,500 4,600 - 4,500 4,600 - 4,600 4,700 - 4,600 4,700 - 4,700 4,800 - 4,700 4,800 - 4,800 4,900 - 4,800 4,900 - 4,900 5,000 - 4,900 5,000 - 5,000 5,100 - 5,000 5,100 - 5,100 5,200 - 5,100 5,200 - 5,200 5,300 - 5,200 5,300 - 5,300 5,400 - 5,300 5,400 - 5,400 5,500 - 5,400 5,500 - 5,500 5,600 - 5,500 5,600 - 5,600 5,700 - 5,600 5,700 - 5,700 5,800 - 5,700 5,800 - 5,800 5,900 - 5,800 5,900 - 5,900 6,000 - 5,900 6,000 - 6,000 6,100 - 6,000 6,100 - 6,100 6,200 - 6,100 6,200 - 6,200 6,300 - 6,200 6,300 - 6,300 6,400 - 6,300 6,400 - 6,400 6,500 - 6,400 6,500 - 6,500 6,600 - 6,500 6,600 - 6,600 6,700 - 6,600 6,700 - 6,700 6,800 - 6,700 6,800 - 6,800 6,900 - 6,800 6,900 - 6,900 7,000 - 6,900 7,000 - 7,000 7,100 - 7,000 7,100 - 7,100 7,200 - 7,100 7,200 - 7,200 7,300 - 7,200 7,300 - 7,300 7,400 - 7,300 7,400 - 7,400 7,500 - 7,400 7,500 - 7,500 7,600 - 7,500 7,600 - 7,600 7,700 - 7,600 7,700 - 7,700 7,800 - 7,700 7,800 - 7,800 7,900 - 7,800 7,900 - 7,900 8,000 - 7,900 8,000 - 8,000 8,100 - 8,000 8,100 - 8,100 8,200 - 8,100 8,200 - 8,200 8,300 - 8,200 8,300 - 8,300 8,400 - 8,300 8,400 - 8,400 8,500 - 8,400 8,500 - 8,500 8,600 - 8,500 8,600 - 8,600 8,700 - 8,600 8,700 - 8,700 8,800 - 8,700 8,800 - 8,800 8,900 - 8,800 8,900 - 8,900 9,000 - 8,900 9,000 - 9,000 9,100 - 9,000 9,100 - 9,100 9,200 - 9,100 9,200 - 9,200 9,300 - 9,200 9,300 - 9,300 9,400 - 9,300 9,400 - 9,400 9,500 - 9,400 9,500 - 9,500 9,600 - 9,500 9,600 - 9,600 9,700 - 9,600 9,700 - 9,700 9,800 - 9,700 9,800 - 9,800 9,900 - 9,800 9,900 - 9,900 10,000 - 9,900 10,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 Legend

g_basin '2000$'.c0DINyld

0 - 50 51 - 100 110 - 150 160 - 200 210 - 250 260 - 300 310 - 350 360 - 400 410 - 450 460 - 500 510 - 550 560 - 600 610 - 650 660 - 700 710 - 750 760 - 800 810 - 850 860 - 900 910 - 950 960 - 1,000 1,100 - 1,100 1,200 - 1,100 1,200 - 1,200 1,300 - 1,200 1,300 - 1,300 1,400 - 1,300 1,400 - 1,400 1,500 - 1,400 1,500 - 1,500 1,600 - 1,500 1,600 - 1,600 1,700 - 1,600 1,700 - 1,700 1,800 - 1,700 1,800 - 1,800 1,900 - 1,800 1,900 - 1,900 2,000 - 1,900 2,000 - 2,000 2,100 - 2,000 2,100 - 2,100 2,200 - 2,100 2,200 - 2,200 2,300 - 2,200 2,300 - 2,300 2,400 - 2,300 2,400 - 2,400 2,500 - 2,400 2,500 - 2,500 2,600 - 2,500 2,600 - 2,600 2,700 - 2,600 2,700 - 2,700 2,800 - 2,700 2,800 - 2,800 2,900 - 2,800 2,900 - 2,900 3,000 - 2,900 3,000 - 3,000 3,100 - 3,000 3,100 - 3,100 3,200 - 3,100 3,200 - 3,200 3,300 - 3,200 3,300 - 3,300 3,400 - 3,300 3,400 - 3,400 3,500 - 3,400 3,500 - 3,500 3,600 - 3,500 3,600 - 3,600 3,700 - 3,600 3,700 - 3,700 3,800 - 3,700 3,800 - 3,800 3,900 - 3,800 3,900 - 3,900 4,000 - 3,900 4,000 - 4,000 4,100 - 4,000 4,100 - 4,100 4,200 - 4,100 4,200 - 4,200 4,300 - 4,200 4,300 - 4,300 4,400 - 4,300 4,400 - 4,400 4,500 - 4,400 4,500 - 4,500 4,600 - 4,500 4,600 - 4,600 4,700 - 4,600 4,700 - 4,700 4,800 - 4,700 4,800 - 4,800 4,900 - 4,800 4,900 - 4,900 5,000 - 4,900 5,000 - 5,000 5,100 - 5,000 5,100 - 5,100 5,200 - 5,100 5,200 - 5,200 5,300 - 5,200 5,300 - 5,300 5,400 - 5,300 5,400 - 5,400 5,500 - 5,400 5,500 - 5,500 5,600 - 5,500 5,600 - 5,600 5,700 - 5,600 5,700 - 5,700 5,800 - 5,700 5,800 - 5,800 5,900 - 5,800 5,900 - 5,900 6,000 - 5,900 6,000 - 6,000 6,100 - 6,000 6,100 - 6,100 6,200 - 6,100 6,200 - 6,200 6,300 - 6,200 6,300 - 6,300 6,400 - 6,300 6,400 - 6,400 6,500 - 6,400 6,500 - 6,500 6,600 - 6,500 6,600 - 6,600 6,700 - 6,600 6,700 - 6,700 6,800 - 6,700 6,800 - 6,800 6,900 - 6,800 6,900 - 6,900 7,000 - 6,900 7,000 - 7,000 7,100 - 7,000 7,100 - 7,100 7,200 - 7,100 7,200 - 7,200 7,300 - 7,200 7,300 - 7,300 7,400 - 7,300 7,400 - 7,400 7,500 - 7,400 7,500 - 7,500 7,600 - 7,500 7,600 - 7,600 7,700 - 7,600 7,700 - 7,700 7,800 - 7,700 7,800 - 7,800 7,900 - 7,800 7,900 - 7,900 8,000 - 7,900 8,000 - 8,000 8,100 - 8,000 8,100 - 8,100 8,200 - 8,100 8,200 - 8,200 8,300 - 8,200 8,300 - 8,300 8,400 - 8,300 8,400 - 8,400 8,500 - 8,400 8,500 - 8,500 8,600 - 8,500 8,600 - 8,600 8,700 - 8,600 8,700 - 8,700 8,800 - 8,700 8,800 - 8,800 8,900 - 8,800 8,900 - 8,900 9,000 - 8,900 9,000 - 9,000 9,100 - 9,000 9,100 - 9,100 9,200 - 9,100 9,200 - 9,200 9,300 - 9,200 9,300 - 9,300 9,400 - 9,300 9,400 - 9,400 9,500 - 9,400 9,500 - 9,500 9,600 - 9,500 9,600 - 9,600 9,700 - 9,600 9,700 - 9,700 9,800 - 9,700 9,800 - 9,800 9,900 - 9,800 9,900 - 9,900 10,000 - 9,900 10,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 10,000 11,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 11,000 12,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000 13,000 - 12,000

0 – 50 51 - 100 100 - 150 151 – 200 201 - 250 251 - 300 301 - 450 451 - 650

> 650 DIN yields (kg km

^-2

year

^-1

)

Fertilizer applications Manure applications Sewage effluents

Fixation over natural areas Deposition over natural areas Fixation over agricultural areas Adapted from Mayorga et al. (2010 ¹ )

Evaluate management measures:

• Buffer strips

• Application timing/rate control

• Alternative tillage practices

• Infrastructural development for grey/black water treatment

• Alternative manure management measures among others

Tang et al. (2012 ⁵ )

NO ₃ ^- fluxes (ton/year)

to stream by SWAT ⁶ Surface runoff 17 Lateral flow 1 Tile flow 1302 base flow 575

Mechanistic

representation in basin-scale

dynamic WQMs

Global Basin

Field/Local

Empirical/statistical/mechanistic methods, e.g., Load _out = R ^F *Load _in

› R ^F = Constant

› R ^F = f(HRT, Q _in , OC _sediment , T, pH, etc.)

› Direct inclusion of basin-scale methods for the dominant processes

Further simplified representation

Riparian wetlands efficiently remove nutrients and pesticides primarily through

sediment trapping, plant uptake and denitrification , but with strong

temporal variabilities.

• Dominant processes in riparian wetlands at spatiotemporal scales relevant for global WQMs

• Critical geophysical parameters influencing the removal rates

Including processes gaining importance with increasing spatial coverage, e.g., atmospheric deposition of volatile pesticides

Hoang et al. (2017 ⁶ )

Regional policy-making

Integrated river basin management plans ^(long-

term strategic decision-making)

Implementation of local

management measures Refining

critical

processes in

global WQ models

Identifying critical

processes and pollution sources

Understanding fundamental processes and mechanisms

Identify hotspots

and trends

Understand mechanisms Assess

management plans

Representative

modeling purposes

Multiscale modeling for WQ management

Multiscale model linking toward refining global WQ models

Spatial coverage

Example models

Global

Basin

Field /Local

Global-NEWS-2 ¹

SWAT ²

DAISY ⁴

APEX ³