I am looking forward to attending Fall Meeting of the American Geophysical Union held this year in Washington D.C. It is always a great way to learn about latest research developments, get to know and meet again interesting people.
I will open the oral session on Hydrochronology: Advances in Tracer Methods and Modeling of Residence Times in Hydrology (H11G) on Monday morning at 8:00 am. The talk on "Towards improved travel time estimates that account for interfaces in the hydrological cycle" will present thoughts and ideas initiated during a Workshop on Water Ages in the Hydrological Cylce held in October 2018. We are currently preparing a review article and I will use the opportunity at AGU to show the current state of our effort to bring together challanges and opportunities for travel time analysis in critical zone science. I will further chair together with Natalie Orlowski, Todd Dawson, and Stephen Good the oral (H22H) and poster session (H22P) on Stable Isotopes in the Critical Zone: Methods, Applications, and Process Interpretations on Tuesday morning and afternoon. I am also involved in Theresa Blume's invited talk on The value of long-term observations for hydrological event response analysis (H11C-07). She will present methods and data we applied and gathered within the CAOS project, in which I was working during my PhD studies.

• Monday, 10 December, 8:00 at Walter E Washington Convention Center - 146A
  Talk: "Towards improved travel time estimates that account for interfaces in the hydrological cycle"
  Sprenger M, Stumpp C, Allen ST, Benettin P, Dubbert M, Hartmann A, Hrachowitz M, Orlowski N, Pfahl S, Rinderer M, Rodriguez N, Werner C, Weiler M

• Monday, 10 December 2018, 9:30 at Walter E Washington Convention Center - 156
  Talk: "The value of long-term observation for hydrological event response analysis"
  Blume T, Beiter D, Demand D, Lieder E, Sprenger M, Weiler M
• Tuesday, 11 December 2018, 10:20 - 12:20 at Convention Ctr - 145B
  Oral Session: "Stable Isotopes in the Critical Zone: Methods, Applications, and Process Interpretations I"
• Tuesday, 11 December 2018, 13:40 - 18:00 at Convention Ctr - Hall A-C (Poster Hall)
  Poster Session: "Stable Isotopes in the Critical Zone: Methods, Applications, and Process Interpretations II Posters"

You are invited to submit your study to a special issue on "Hillslope Hydrology: Towards Improved Process Understanding Using Modeling and/or Field Observations" in the open access journal Water. If you are working currently on a hillslope study and plan to submit the results of your investigations in 2019, please consider this special issue that I organize together with Jaromir Dusek, Ali Ameli, and Shiqin Wang. Deadline for submission will be December 2019 and please do not hesitate to contact us if you have questions. Info can be found on the homepage and in the flyer (PDF download).

We are organizing again a session on "Stable isotopes to study water and nutrient dynamics in the soil-plant-atmosphere continuum" for the European Geoscience Union General Assembly. It will be the third year that we invite abstracts to this topic and we are looking forward to hear about the recent developments in the field of stable isotope applications in soil plant interactions. The session was well-received in the last years with a full room during the interesting talks in our oral session and many inspiring discussions at the posters. We hope to attract once again many scientists and welcome abstract submission until January 10, 2019. ​https://meetingorganizer.copernicus.org/EGU2019/session/31635

I was happy to take part in a seminar on "Isotopes and environmental tracers in hydrology" organized by the Water Resources and Environmental Engineering group at the University of Oulu, Finland. On two days, we heard about latest applications of tracers and discussed recent developments in tracer hydrology. On the third day, I served as an opponent for a PhD defense, which meant that I discussed with the PhD student their thesis over 90 minutes. For the rest of the week, I joined the research group for a field campaign at the Pallas-Yllästunturi-Nationalpark to take for example soil samples for stable isotope analysis and install snow lysimeters. It was a week full of exciting research, great discussions and stunning landscapes. I am looking forward to go back to Finland next year due to funding by the German Hydrolgical Society.

It was a great honor to attend a Symposium on Ecological Restoration and Efficient Utilization of Water Resources in Semi-arid Regions in Zhangjiakou, Hebei Province, China last week. I learned a lot about the issues of water shortage and contamination in Hebei (West and South-West of Beijing). The talks at the symposium presented the conflict between increasing water demand for agricultural and forestation, while the groundwater availability dropped dramatically over the last decades due to the ongoing land use changes. I presented how stable isotopes of water can help to assess the partitioning between green water (used by plants) and blue water (groundwater recharge), which are the grand challenges in semi-arid environments to ensure agriculture production and groundwater availability.

A field excursion to research centers investigating improved irrigation and fertilization practices showed current developments towards recommendations to the government and farmers in the Hebei province in order to mitigate further stress on the water supply.

I was further invited to visit the group of Prof. Shiqin Wang at the Center of Agricultural Resources Research of the Chinese Academy of Sciences in Shijiazhuang, Hebei, China. We visited one of her field sites in the Taihang Mountain and I enjoyed the discussion with her and her students.
The week-long trip allowed an in-depth insight into the current hydrological issues addressed in Chinese research, but also provided a unique experience of Chinese culture, drinks, and food. Thanks to Prof. Shiqin Wang, who made this possible! (Thanks to Shiqin and Yan-Jun for sharing their photos!)

Our study on measuring and modelling the isotopic composition of mobile and bulk soil water published in Vadose Zone Journal got featured in the CSA News of the Alliance of Crop, Soil and Environmental Science Societies. You can read the short abstract here.

Our study on water ages in the soil, transpiration, evaporation and recharge got published in Hydrology and Earth System Sciences after a lively discussion during the open peer-review process. We simulated how long the water travels through the compartments of the critical zone and also the median age of the water in each compartment. We found that the travel time distribution is not necessarily the same for evaporation and transpiration, as the roots access older water in deeper soil layers than the evaporation. Further, the travel time of the recharge flux is mainly driven by flushing events, when there is high recharge during winter (in Scotland) or during snow melt (in Canada and Sweden). Water ages are generally lower the higher the storage and increase with decrease in soil wetness. This is true for recharge and also evaporation and transpiration fluxes. We hope to contribute with this to the ongoing research on how the soil-plant interactions affect the water flow and transport in the upper critical zone. You can download the manuscript here.

I am happy to announce that I just started this week a two-year project on "Water age dynamics in a Mediterranean catchment and their ecohydrological implications in a changing environment" funded by the German Research Foundation (DFG).
I will work together with the team of the Surface Hydrology and Erosion Group of the Institute of Environmental Assessment and Water Research (IDAEA-CSIC) in Barcelona on their extensive data set gathered in the Vallcebre Research Catchments (an overview of the impressive research and data sets from the IDAEA group can be found here). We will use hydrometric and stable isotope data from various hydrological compartments (precipitation, stream, groundwater, soils, plants) to assess travel times across the catchment with latest modeling approaches to improve the understanding of storage and release of water in the highly seasonal environment of the headwater catchment contributing to the water supply of the Barcelona area. If you are interested what we will be doing in the coming two years, you can follow project updates on researchgate.

I look forward to organizing a session for the AGU Fall Meeting 2018 with Natalie Orlowski, Todd Dwason, and Stephen P Good on "Stable Isotopes in the Critical Zone: Methods, Applications and Process Interpretations".
If you use stable isotopes to study the Earth's Critical Zone, we would be happy to receive your abstract before 1st of August here.

The special section on "Stable isotope approaches in vadose zone research" in Vadose Zone Journal is complete and online as open access here, including our study on "Measuring and modelling stable isotopes of mobile and bulk soil water".