1. SPP 1257 1 STREMP Results STREMP STREMP quantifies regionally the mass transport between hydrosphere, ocean and atmosphere. It provides an assessment of regional mass transport. Results: 1. ocean water mass variation 2. steric component 3. straits flow 4. mass variation on land 5. improved hydrology model 6. improved ocean model Fig. 2. Improved ocean model: 2 nd EOF of steric component from free (red line) and assimilation runs. Figure 4. Net flux at Gibraltar (left) and at Bosphorus (right) as equivalent water change in Mediterranean and Black Sea respectively. Fig.1. WaterGAP3 compared to semi-climatological total river runoff (left) and to global model (right). Figure 3. Sea level and its components in MED Sea

2. SPP 1257 2 STREMP REGHYDRO GRACE solution improved by regional de-aliasing model IMPLY GRACE solution improved by regional de-aliasing model WP 100 - TUD Multi-mission altimetry retracked altimetry coast and land steric-corrected altimetry mean sea level WP 200 - TUD + IGG GRACE post-processed solutions GOCE geoid solution WP 500 MDT from NEMO Mass variation/straits flow WP300 - ICBM NEMO assimilated model BS WP 400 - CESR WaterGAP3 assimilated model with GRACE, altimetry, SMOS Steric from T, S from model Altimetry, MDT for assimilation GOCE to compute MDT River runoff for assimilation GRACE for WaterGAP3 calibration GRACE solution, mean de-aliasing fields 6 hourly ocean bottom pressure Daily total water storage DAROTA ocean tide model EOT10 TOPO-EUROPE RATSEL-GRACE GRACE regional solution JIGOG GRACE weekly solutions geocenter motion surface loading WATERGAP TASMAGOG Vernetzung / Gewinn des Projektes in SPP / Einordnung in die Themen Steady-state & long-term processes Short-term processes Understanding the satellite signal

3. SPP 1257 3 STREMP Visionen / offene Fragen für Phase 3 1. GRACE: which are the real spatial resolution limits of mass change estimation? 2. DE-ALIASING: what is the impact of different de-aliasing on the solutions? We will evaluate it using our regional models in the de-aliasing. 3. CORRECTIONS: the atmospheric correction applied to altimetry (MOG2D) is not fully compatible with corrections/de-aliasing used in GRACE. What is the effect on the two estimations of mass change? 4. OCEANOGRAPHY/HYDROLOGY: how to validate the models after data assimilation? 5. HYDROLOGY: GRACE cannot distinguish between different hydrological compartements. Can we separate the different compartments using external information? Interaction & coupling of the dedicated regional hydrology & ocean models - Data assimilation plays a very important role in constraining the models - The closure error validates mass variation & transport estimates Open questions: