Spatial dynamics and consistency of agroclimatic trends in Chile during 1985-2015 to the Köppen-Geiger climate classification

Raul Orrego-Verdugo1*, Rodrigo Abarca-del-Rio2, and Claudia Lara-Uribe3
The Köppen-Geiger classification is one of the most common climate classification systems in the world. It allows classifying ecosystem distribution based on temperature and precipitation, two critical factors in climate, and vegetation cover's sensitivity. We analyzed the dynamics and spatial consistency of agroclimatic variables in each type of Köppen-Geiger climate present in Chile, visualizing the variables' behavior throughout the territory. Thus, we computed the trends of different climate and agroclimatic variables in each meteorological station, mapping their slope and statistical significance, and comparing their sense among all those that belong to the same climate zone. Our global trends analysis showed a thermal amplitude decrease in northern and central areas in about 12.03% and 20.3%, respectively, and an increase in south and southern areas in about 13.7% and 26.3%. A generalized increase in frost events (2.90%-16.02%) took place mainly in the country's northern part. Results showed higher concordance percentages in stations belonging to the Köppen-Geiger type B (dry climate) and C (temperate climate). Thus, an increase in the maximum temperature occurred from north-central to south zones, a decrease in minimum temperature from north to central zone, and an increase in highlands (700-4000 m a.s.l.), central, south, and southern zone of the country. Also, a precipitation decrease and thermal amplitude increased roughly from the Coquimbo Region to the country's central and southern zone. Variations in the agroclimatic indices' behavior can affect yield and production of crops; thus, agroclimatic information presented here can support the zoning and selection of the cropping system.
Keywords: Agroclimatic indexes, climate change, climate variables, Köppen-Geiger climate, precipitation and temperature trends.
1Instituto de Investigaciones Agropecuarias, INIA Quilamapu, Av. Vicente Méndez 515, Chillán, Chile.
*Corresponding author (raul.orrego@inia.cl).
2Universidad de Concepción, Facultad de Ciencias Físicas y Matemáticas, Av. Esteban Iturra s/n, Concepción, Chile.
3Universidad del BíoBío, Facultad de Ciencias Básicas, Av. Andrés Bello 720, Chillán, Chile.