Dr. Rehana Shaik gave an invited talk on Hydrology under Climate Signals at Various Spatial and Temporal Scales: Challenges at a Discussion Meeting on  Hydrology in the Anthropocene held at Interdisciplinary Centre for Water Research, Indian Institute of Science, Bangalore (IISc Bangalore) from 6 – 9 December.

The workshop on Hydrology in the Anthropocene was conceptualised by Prof. Ana Mijic, Imperial College London (Satish Dhawan Chair) and Prof. P P Mujumdar, Interdisciplinary Centre for Water Research, IISc Bangalore. The discussions spread over the course of three days and were held in the picturesque Hoysala Village Resort in the quaint town of Hassan. Several potential science questions related to human interactions with nature and water cycle feedback were collated and prioritized.

Here is the summary of Dr. Rehana Shaik’s talk:

• Hydrology under climate signals at various spatial and temporal scales can be effectively studied using driving forces along with global circulation model outputs/ reanalysis data/ gridded data/ remote sensing data/gauging station data.

• Climate change impacts on regional evapotranspiration flux and variability of climatological and hydrological droughts can be assessed by drought indices like the Standardised Precipitation Evapotranspiration Index (SPEI) and the Standardised Precipitation Actual Evapotranspiration Index (SPAEI).

• The SPAEI can provide more insight into capturing the severe and extreme drought characteristics at catchment scales compared to the SPEI due to the inclusion of hydrologically induced AET in the drought characterization instead of PET.

• Actual evapotranspiration can be promising toward drought intensity, extreme drought areal extents, shorter‐time scale drought frequencies, and longer‐time scale drought durations for water‐limited zones (P<PET) compared to energy-limited zones (P>PET).

• Validation of water quantity-quality modelling results is challenging due to the spatiotemporal mismatch between hydrological, meteorological data, and pollution monitoring networks for Indian rivers.

• A holistic approach to integrating water quantity and quality to identify the possible contamination levels and measures for policymaking is required.

• For every 1 °C rise in river water temperature due to climate change, there will be about a 2.3% decrease in dissolved oxygen saturation level concentrations over Indian catchments under climate signals.