2nd meeting

Minutes from the 2nd CHIHE Workshop, held on the 20th -21st of January 2015, at the Norwegian Water and Energy Directorate (NWE), Oslo.

Present: Hege Hisdal, Deborah Lawrence, Ewa Bogdanowicz, Renata Romanowicz, Marzena Osuch, Joanna Doroszkiewicz, Hadush Meresa, Jaroslaw Napiorkowski

In addition, there were also present Wai Wong and Heidi Lee from the NWE at the meeting.

Workshop was opened by Deborah Lawrence, followed by the introduction presented by Renata Romanowicz.

Renata gave a short presentation of the aims of the meeting, which were a summary of the first year of the project, achieved mail-stones and deliverables in all WPs according to the Project plan. Workshop additional outcomes were as follows:  

·         selection of bias correction methods;

·         selection of hydrological models;

·         discussion on the criteria of hydrological model calibration for low and high flows.

In addition, a summary of the present status of students’ work, Joanna, Hadush and Sisay Debele, towards their PhDs was to be assessed.

The report on the progress in WP1 was given by Jaroslaw.  The first year of the project in this WP1 was focused on the selection of eight Polish and Norwegian catchments as case studies. The results were presented in two Reports. The first one, “Hydrological Catchment Selection in Poland for Climate Change Impact Studies” was written by Hadush, Marzena and Jaroslaw, the second, was prepared by Donna Wilson and was related to the choice of Norwegian catchments. In a result ten hydrological catchments were selected for Poland and eight for Norway.

The other important part of the research was performed together with the other WPs, on the choice of hydro-meteorological  indices for climate change impact studies.  Among the topics discussed, related to the choice of catchments, were the availability of data related to the land cover and elevation  data in Norway and Poland, spatial distribution of time series, tests on time-series homogeneity (temperature and precipitation) and HBV model conceptualization scheme applied in the Norwegian studies.

The next WP1 task is focused on trend, homogeneity and correlation analyses of observed temperature, precipitation and discharge parameters for each of the selected Norwegian and Polish catchments.  This deliverable is due at the end of 2015.

The report on WP2 progress was presented by Deborah. The HBV model conceptualization, that takes into account variations in elevation and application of gridded (2x2 km2) input data (temperature and precipitation), prepared by the Norwegian Met-Office was one of the discussed topics. The work in this WP2 concentrated on the downloading and preparation of ENSEMBLES and EUROCORDEX data sets, performed by Marzena and Hadush.

The report on WP3 was presented by Ewa.  The work in this WP3 concentrated on the ML estimation in the presence of covariates and so called two-stage estimation, Non-stationary multi-model approach to the extreme value modeling, DqF and QdF approaches to high and low flows, Copulas in seasonal approach and copula based time series models. Among the discussed problems there were differences between drought and flood processes to be also discussed from the point of view of DqF and QdF approaches and analysis of dependent/independent seasonal maxima (minima) performed by  Sisay.

Hege Hisdale presented the report on the WP4 progress – climate change adaptation in Poland and Norway. The first task of this WP4 was the identification of flood management  measures and type of constructions, overview of policy and laws (suitable) for adaptation. The report on that issue was prepared by Joanna and it forms the background of her first PhD paper under preparation.

The discussion that followed included

·         Eurocordex data

·         Norway has 1x1km grided datasets of precipitation and temperature over the whole country

·         Question on gridded data against point –station data

·         Eobs data

In the afternoon, the discussions followed on the current and future work in the WPs. These included:

Trend analysis presented by JJN in the form of a  review of work done on monthly data trend analysis by prof.  Mitosek. Trend analysis was performed using different significance tests. Dynamic Harmonic Regression (DHR) was presented by Renata.

After a discussion it was decided to apply three methods : Man Kendall test, DHR, Wavelets, to both Norwegian and Polish data

In the following part of the meeting the research on summer droughts in Norway was presented by Wai Wong. The presentation included a discussion of differences in summer and winter droughts due to different conditions.

Marzena gave the presentation on SPI indices, based on Prague Conference talk. The research showed that different results are obtained for raw and bias-corrected data, which indicates the importance of bias correction methods to preserve trend. Precipitation and temperature can be corrected using the change factor (subtract the bias and multiply, respectively). HESS 2013 – Hempel et al.

Deborah Lawrence gave a presentation on bias correction methods, including the issues of preserving high and low flows, correlation between T and P, validation of bias correction methods, issue for extreme indices, perturbation method for extremes – Patrick Willems (?), bias correction using Copula and multivariate quantile mapping – [Piani, XX]. It was suggested that Double Gamma distribution should be applied in WP2 as it gives good results in bias correction.

 

Non-stationarity issues were discussed by  Marzena, who presented an article on the application of regression models applied to describe relation between parameters and climate indices (presented in Potsdam);

Ewa gave a presentation on quantile regression – introducing index on upper or lower quantile indices. Ewa asked if there were any physical reasons for correlation between precipitation and temperature; weather patterns – will they change?

Wednesday, 21.01.2015

This part of the meeting had three main topics planned for a discussion: Adaptation policy and instruments in Poland (Joanna, Renata); Discussion on the adaptation techniques in Norway (Hege); Discussion on the CHIHE web-page and promotion (Renata)

Hege presented  an application of adaptation techniques in Norway, which included Median used as potential change, spread – probability; Municipalities do not want to see probabilities; Classification of changes into 3 groups (0, 20% and 40% change); Differences between Poland and Norway – much less dense population.

In the discussion on the web page the following was decided :

-          Prepare web page in Polish

-          Web page as a deliverable in WP4 – target groups and dialog

-          Put links to the powodz.gov.pl and naukaoklimacie.pl web-pages

One picture for About web-page – very dry Vistula River + flood

-          List of project participants+ links to the personal web-pages

Next part of the meeting considered the Conference plans. Among the interesting conferences are:

1.       EGU 2015, April, Vienna, Austria

2.       IUGG 2015, June, Prague, Czech Republic

3.       3rd Conference on Modelling Hydrology, Climate and Land Surface Processes, September 7-9, 2015, Lillehammer, Norway, co-organised by NWE

The last part of the meeting consisted of a general discussion on the present status of PhDs of the students and separate discussions within the working groups.

1.       PhD thesis: Hadush:

-          Drought projection using hydro-meteorological indices: PDSI and PSI

-          Review, testing and application of downscaling/bias correction techniques

-          Analysis of uncertainty due to differences in downscaling, climate projections and hydrological modelling

2.       PhD thesis: Joanna

1.       Laws and policies  in Poland and Norway

2.       Derivation of flood risk maps under different scenarios (hydraulic modelling)

3.       Comparison of various sources of uncertainty in flood risk assessment in future climate