Model-based reconstruction and projections of soil moisture anomalies and crop losses in Poland

Abstract

Evidence shows that soil moisture (SM) anomalies (deficits or excesses) are the key factor affecting crop yield in rain-fed agriculture. Over last decades, Poland has faced several major droughts and at least one major soil moisture excess event leading to severe crop losses. This study aims to simulate the multi-annual variability of SM anomalies in Poland, using a process-based SWAT model and to assess the effect of climate change on future extreme SM conditions, potentially affecting crop yields in Poland. A crop-specific indicator based on simulated daily soil moisture content for the critical development stages of investigated crops (winter cereals, spring cereals, potato and maize) was designed, evaluated for past conditions against empirical cropweather indices (CWIs), and applied for studying future climate conditions. The study used an ensemble of nine bias-corrected EURO-CORDEX projections for two future horizons: 2021-2050 and 2071-2100 under two Representative Concentration Pathways: RCP4.5 and 8.5. Historical simulation results showed that SWAT was capable of capturing major SM deficit and excess episodes for different crops in Poland. For spring cereals, potato and maize, despite a large model spread, projections generally showed increase of severity of soil moisture deficits, as well as of total area affected by them. Ensemble median fraction of land with extreme soil moisture deficits, occupied by each of these crops, is projected to at least double in size. The signals of change in soil moisture excesses for potato and maize were more dependent on selection of RCP and future horizon.

Severe Drought in the Spring of 2020 in Poland—More of the Same?

“…Extreme droughts from the past, e.g., those recorded in 2003, 2010, 2015 and 2018-2019, will no longer be classified as extreme in Europe. Without effective climate change mitigation, large areas of Europe may be affected by soil moisture deficits [3,20,21].…”

“…In Poland, where rain-fed agriculture has been prevailing, soil moisture deficits are the main factor adversely affecting the agricultural productivity. Droughts as severe as those that occurred in Poland in 2015, 2018 and 2019 are projected to be more frequent in the future and to affect larger areas [21].…”

Temperature Changes and Their Impact on Drought Conditions in Winter and Spring in the Vistula Basin

“…In Poland rain-fed agriculture has been prevailing and soil moisture deficits, especially in the spring season, lead to a significant decrease in agricultural productivity. According to Piniewski et al [18] droughts as severe as those that occurred in Poland in 2015, 2018 and 2019 are projected to be more frequent in the future and to affect larger areas.…”

Soil drought and circulation types in a longitudinal transect over central Europe

“…Piniewski et al . (2020) modelled soil moisture changes in Poland for the 21st century using EURO‐CORDEX projections and investigated their impacts on crop yields.…”

“…Ruosteenoja et al (2018), applying CMIP5 projections of seasonal soil moisture and drought occurrence in Europe for the 21st century, found pronounced soil drying for western and central Europe in summer and autumn. Piniewski et al (2020) modelled soil moisture changes in Poland for the 21st century using EURO-CORDEX projections and investigated their impacts on crop yields.…”