  Ensuring food supply stability is key to food security for economies, and
food imports become increasingly important to safeguard food supplies in
economies with inadequate food production. Food import shocks have significant
impacts on targeted economies. Using import trade data of four staple crops
(maize, rice, soybean, and wheat) from 1986 to 2018, this paper identifies food
import trade shocks that occurred to economies during the period of 1995--2018.
We compare the temporal evolution and spatial distribution of import shocks
occurring to different crops and analyze the shock intensity and shock recovery
in various continents based on locally weighted polynomial regression and
Cook's distance. The results reveal higher frequencies during the 2007/2008
food crisis and relatively higher shock frequencies in North America, Africa,
and Asia. Meanwhile, there are regional differences in shock recovery, with the
majority of shocks in Asia recovering in the short term. We also find that high
import diversity and a low import dependency ratio buffer economies against
import shocks, resulting in a low shock rate and a high recovery rate. These
results contribute to our understanding of the external supply risks of food,
placing emphasis on accessibility issues in food security.
