Akademik Veri Yönetim Sistemi
XXIX INTERNATIONAL SYMPOSIUM ON MODERN TECHNOLOGIES, EDUCATION AND PROFESSIONAL PRACTICE IN GEODESY AND RELATED FIELDS, İstanbul, Türkiye, 5 - 06 Kasım 2019, ss.24-33
Drought is a long-lasting shortage in water supply in the atmosphere, surface and groundwater
expressing itself with (i) less than average precipitation (meteorological drought), (ii) followed
by a damage in crop production or in the ecology, if below-average precipitation period is
extended (agricultural drought) and also with (iii) significant fall of water reserves such as in
aquifers, lakes (hydrological drought). Thus, drought monitoring is crucial for the economy and
water resources management for a country, however, it cannot be achieved properly in national
scale with the traditional observation methods. Satellite-based techniques for drought
monitoring are very promising for this purpose. In this study, by using Center for Space
Research (CSR)’s Level 3, Release 5 (RL05) data observed by Gravity Recovery and Climate
Experiment (GRACE) satellite, German Research Center (GFZ)’s Level 3, Release 6 (RL06)
data observed by GRACE/GRACE-FO (GRACE-Follow-On) satellite, Tropical Rainfall
Measuring Mission (TRMM) precipitation data, Global Land Data Assimilation System
(GLDAS) data and finally drought indices (El Niño–Southern Oscillation: ENSO, North
Atlantic Oscillation: NOA, Self-calibrating Palmer Drought Severity index: SCPDSI), a state
of the art about drought monitoring in Turkey, is presented. The results propose to find answers
about how to reveal the dominant drought periods, get notable information about the spatial
distribution, observe spatial and temporal change rate and understand several prominent reasons
of the drought events observed in Turkey. Moreover, the results of the statistical approach used
for the prediction of GRACE/GRACE-FO derived Total Water Storage (TWS) time series is
discussed. According to our results, the spatial distribution of the drought is primarily affected
by the precipitation history but also by uncontrolled human usage of water resources, especially
in Central Anatolia according to GRACE and GRACE-FO results. The contrast leading to a
spatial change from Eastern part to Western part, with a rate of 1 cm/yr, is less obvious
according to GRACE-FO derived amplitude of TWS section. Recent, GRACE-FO amplitude
sections of TWS shows in the general sense, the increasing impact of drought observed in
Turkey.