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This white paper reviews the scientific community's ability to use data from future telescopes to search for life on exoplanets. It summarizes products from the Exoplanet Biosignatures Workshop Without Walls (EBWWW). This effort led to papers that constituted the Exoplanet Analysis Group's (ExoPAG) 16th Science Assessment Group (SAG 16).

Throughout its historical development, hydrology as an earth science, but especially as a problem-centred engineering discipline has largely relied (quite successfully) on the assumption of stationarity. This includes assuming time invariance of boundary conditions such as climate, system configurations such as land use, topography and morphology, and dynamics such as flow regimes and flood recurrence at different spatio-temporal aggregation scales. The justification for this assumption was often that when compared with the temporal, spatial, or topical extent ofthe questions posed to hydrology, such conditions could indeed be considered stationary, and therefore the neglect of certain long-term non-stationarities or feedback effects (even if they were known) would not introduce a large error. However, over time two closely related phenomena emerged that have increasingly reduced the general applicability of the stationarity concept: the first is the rapid and extensive global changes in many parts of the hydrological cycle, changing formerly stationary systems to transient ones. The second is that the questions posed to hydrology have become increasingly more complex, requiring the joint consideration of increasingly more (sub-) systems and their interactions across more and longer timescales, which limits the applicability of stationarity assumptions. Therefore, the applicability of hydrological concepts based on stationarity has diminished at the same rate as the complexity of the hydrological problems we are confronted with and the transient nature of the hydrological systems we are dealing with has increased. The aim of this paper is to present and discuss potentially helpful paradigms and theories that should be considered as we seek to better understand complex hydrological systems under change. For the sake of brevity we focus on catchment hydrology. We begin with a discussion of the general nature of explanation in hydrology and briefly review the history of catchment hydrology. We then propose and discuss several perspectives on catchments: as complex dynamical systems, self-organizing systems, co-evolving systems and open dissipative thermodynamic systems. We discuss the benefits of comparative hydrology and of taking an informationtheoretic view of catchments, including the flow of information from data to models to predictions. In summary, we suggest that these perspectives deserve closer attention and that their synergistic combination can advance catchment hydrology to address questions of change.

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The new Scientific Decade 2013–2022 of IAHS, entitled “Panta Rhei—Everything Flows”, is dedicated to research activities on change in hydrology and society. The purpose of Panta Rhei is to reach an improved interpretation of the processes governing the water cycle by focusing on their changing dynamics in connection with rapidly changing human systems. The practical aim is to improve our capability to make predictions of water resources dynamics to support sustainable societal development in a changing environment. The concept implies a focus on hydrological systems as a changing interface between environment and society, whose dynamics are essential to determine water security, human safety and development, and to set priorities for environmental management. The Scientific Decade 2013–2022 will devise innovative theoretical blueprints for the representation of processes including change and will focus on advanced monitoring and data analysis techniques. Interdisciplinarity will be sought by increased efforts to connect with the socio-economic sciences and geosciences in general. This paper presents a summary of the Science Plan of Panta Rhei, its targets, research questions and expected outcomes.

An evaluation of the performance of a range of techniques for the measurement of the concentration of trace level organic contaminants was undertaken in the River Glomma during the period August-November 2010. This work focussed on further evaluating two techniques that have the potential to substantially improve the reliability and limits of detection of such measurements. Passive sampling devices, namely low density polyethylene membranes and silicone strips, were deployed over three consecutive 28 day periods to measure dissolved concentrations of polycyclic aromatic hydrocarbons, polychlorinated biphenyls and brominated flame retardants. Continuous flow centrifugation was used to measure these contaminants associated with the particulate phase. Contaminant limits of detection were in the low pg L-1 range or below. These methods have the potential to become a vital part of the Riverine Input and Discharge (RID) monitoring programme for the evaluation of riverine fluxes of contaminants to the North Sea and to help with responding to the challenges set by the EU Water Framework Directive (WFD). A set of recommendations for the use of these techniques for such monitoring tasks is given. Klima- og forurensningsdirektoratet (Klif)

The report presents results from the Water Column Monitoring 2009, performed in collaboration between NIVA and IRIS, with sub-contractors. The objective of the survey was to assess the extent to which produced water discharges from Ekofisk affect organisms living in the water column. The study was designed to monitor bio-accumulation and biomarker responses in organisms held in cages in the vicinity of the water discharge point(s). The study design was identical to that carried out at Ekofisk in 2006 and 2008 with only minor modifications where necessary. The implementation of a produced water treatment system (C-Tour), operational in 2008, aimed to reduce the output of potentially toxic chemicals into the surrounding water column. The monitoring surveys performed pre and post implementation of C-Tour, were designed to assess whether changes in animal health status between the different years have occurred. The results of the 2009 survey have shown that caged organisms were exposed to low levels of produced water components with highest tissue concentrations in mussels Mytilus edulis, located closest to the produced water discharge. Mussels located approximately 1-2 km away showed only background concentrations of the organic compounds measured. Concentrations of polycyclic aromatic hydrocarbon (PAH) and alkyl phenol (AP)-metabolites in bile of caged cod Gadus morhua, were slightly elevated suggesting exposure at the Ekofisk stations. There was a signal of exposure with proximity to the discharge for some of the biomarkers measured including CYP1A in fish and micronuclei in mussels. However, all other fish and mussel biomarkers showed no significant exposure effects. The bioaccumulation data and biomarker responses indicated a lower exposure to the produced water effluent than seen previously in 2008 and 2006. The volume of produced water discharged to the investigated area increased in 2009 from 2008 and 2006. However, the amount of oil discharged with the produced water was less, resulting in an overall reduction of oil to the local area. This reduction in oil discharge was reflected in the bioaccumulation and biomarker data, resulting in a general improvement in the health of caged mussels and fish in 2009 compared to 2008 and 2006. Overall, based on the bioaccumulation and biomarker data in 2009, the current environmental risk of the PW on animals living in the water column in proximity to the platforms is low. ConocoPhillips on behalf of the OLF WCM coordination group

A performance evaluation of a range of techniques for the measurement of the concentration of persistent organic pollutants and trace metals was undertaken in the Rivers Glomma and Drammen in 2009. This work focussed on further evaluating techniques that have the potential to substantially improve the reliability and limits of detection of such measurements. Passive sampling techniques were employed to measure dissolved concentrations of polycyclic aromatic hydrocarbons, polychlorinated biphenyls and brominated flame retardants while continuous flow centrifugation and time-integrative suspended particulate matter samplers were used to measure contaminants associated with the particulate phase. Contaminant limits of detection were in the low pg L-1 range or below and significant improvements in the sampling procedures and in the reliability of the data were observed. These methods have the potential to become a vital part of the RID monitoring programme for the evaluation of riverine fluxes of contaminants to the North Sea. Klima- og forurensningsdirektoratet (Klif)

The mussel, Mytilus edulis has been used to assess the biological effects of produced water (PW) discharged from the Ormen Lange gas processing plant on the West coast of Norway. An integrated monitoring approach was applied, using a combination of sensitive health index parameters in the mussel including lysosomal membrane stability (LMS) and micronuclei (MN) formation in haemocytes of live mussels, cell type composition, lysosomal membrane stability and peroxisome proliferators in mussel digestive gland, and contaminant body burden concentrations in whole tissue homogenates. In addition, semipermeable membrane devices (SPMDs) were used to support the biological effects data. The biological and chemical endpoints were measured in mussels from three different exposure scenarios: 1) native mussels found on the shore in the vicinity of the produced water discharge point; 2) mussels placed in cages at known distances from the produced water discharge point; and 3) mussels exposed to known concentrations of produced water in a laboratory controlled flow-through dosing system. The results of the biological effects data and chemical analysis are presented. For the native shore mussels, good agreement between biological effects measurements was observed. Mussels located at sites closest to Ormen Lange showed clear stress responses indicative of poor health status, compared to the reference mussels. For the caged mussels, contradictory biological effects measurements were found, which were thought partly due to the overall poor health of the mussels used. Consequently no firm conclusions were drawn about the cage exposure. In the controlled laboratory exposure to PW, biological effects were found in mussels exposed to 0.01% PW and above compared to a control group. Overall, although some were anomalous, the results indicate that Ormen Lange PW may have detrimental effects on mussel health. Norske Shell, Det Norske Veritas v/ Tormod Glette

Årsliste 2008 Høsten 2007 ble det gjennomført en studie av forekomst av polyaromatiske hydrokarboner (PAH), organiske tinnforbindelser (Sn-org) og polyklorerte bifenyler (PCB) i vannfasen på fire steder i Nidelvsystemet. Det ble også samlet inn lakseyngel (1+- 2+ Salmo salar) for analyse av Sn-org. I tillegg mottok NIVA 14 sedimentprøver og 15 sandbankprøver fra NGU som ble analysert for Sn-org. Disse er rapportert særskilt. Nivåene i vann av PAH varierte mellom 1,7 – 16,3 ng L-1. Det ble ikke detektert PCB eller Sn-org i vannfasen. I fiskelever varierte tributyltinn (TBT) mellom < 1 – 1,9 ng g-1 v.v. For dibutyltinn (DBT) i fiskelever var konsentrasjonene høyere enn for TBT og varierte mellom 4,5 – 12 ng g-1 v.v. Det er ikke urimelig å anta at disse konsentrasjonsforskjellene reflekterer en ulik forurensningsbelastning. Resultatene fra undersøkelsen viser at bidraget av PAH, PCB og Sn-org, fra Nidelva til Trondheim havn er begrenset. Trondheim kommune

Årsliste 2007 Spredning av miljøgifter fra deponiområdet ved Malmøykalven ble undersøkt ved eksponering av passive prøvetakere i vannmassene i Indre Oslofjord i perioden 10.05.-12.06.2007. Spredningen av partikler ble samtidig sporet ved å undersøke innholdet av bentiske gruntvannsforaminiferer i sedimenter fra Bekkelagsbassenget, i og utenfor deponimrådet. Undersøkelsen viste at organiske foringer fra foraminiferer er transportert til deler av Bekkelagsbassenget utenfor deponiområdet. Imidlertid er det usikkert i hvilken grad denne spredningen kan representere spredning av sedimentpartikler. De passive prøvetakerne viste lave konsentrasjoner av kadmium, sink og kopper i nærheten av deponiområdet. Konsentrasjonene av bly og PAH var høyere i deponiområdet enn på referensestasjonene i Bunnefjorden og Vestfjorden, men lavere enn i Havnebassenget. Detekterbare mengder av PCB ble bare unntaksvis observert utenfor Havnebassenget. Spredning av miljøgifter fra deponiområdet oppover til terskeldypet i Bekkelagsbassenget beregnet på grunnlag av de målte konsentrasjonene, var tilsvarende eller mindre enn beregnet før arbeidene ble startet. Sammenlignet med målingene i Havnebassenget syntes påvirkningen fra deponiområdet under normale hydrografiske forhold å være relativt ubetydelig. I tillegg vil spredningen fra deponiområdet være midlertidig til arbeidene avsluttes og deponiet overdekkes med rene masser. Statens Forurensningstilsyn

Large volumes of produced water are released into the North Sea and there is still some uncertainty as to the environmental impacts. Following the BECPELAG workshop in 2001-2002, water column monitoring near selected platforms has been performed using a combination of chemical and biological effects methods. The aim of the present study was to investigate some new candidate biomarker methods. At the two chosen exposure levels, 4300- and 137000-fold diluted produced water, PAH concentrations in exposed blue mussels were similar to those found following deployment offshore. PAH bile metabolites in cod were not significantly increased. There was a clear response in micronucleus formation in mussel haemocytes. Other methods that could become useful for monitoring in the future included mixed xenobiotic defence (MXR) components in cod red blood cells, peroxisomal effects in mussel and cellular energy allocation in mussel. No exposure-related effects were seen for glutathione S-transferase in either species or MXR in blue mussel haemocytes.

Årsliste 2006 Rapporten gjør rede for undersøkelser utført for å avklare om miljøgifter kan ha betydning for bestanden av elvemusling i Haukåselva. Det ble målt organiske miljøgifter (PCB, DDT, PAH) i vannprøver, i elvemuslinger og vha. passive prøvetakere. Uorganiske elementer ble målt i vannprøver og muslinger. Resultatene er sammenholdt med tidligere målinger på organiske sedimentavsetninger i vassdraget. Resultatene tyder på at PAH er den eneste gruppen av de undersøkte miljøgifter som kan tenkes å ha betydning for muslingene. PAH ble påvist i lave konsentrasjoner i vannfasen. PAH målt i muslinger tyder imidlertid på at disse får i seg stoffene først og fremst via organiske partikler som filtreres fra vannet og spises. Det er tidligere påvist betydelige tilførsler av både partikler og PAH i den øvre del av vassdraget. De nye resultatene tyder på at også den nedre del av vassdraget får PAH-tilførsler. Tiltak som reduserer partikkeltilførsler vil også redusere hoved-belastningen med PAHer for muslingene. Bergen kommune

Årsliste 2006 Large volumes of produced water are released into the North Sea and there is still some uncertainty as to the environmental impacts. Following the BECPELAG workshop in 2001-2002, water column monitoring near selected platforms has been performed using a combination of chemical and biological effects methods. The aim of the present study was to investigate some new candidate biomarker methods. At the two chosen exposure levels, 4300- and 137000-fold diluted produced water, PAH concentrations in exposed blue mussels were similar to those found following deployment offshore. PAH bile metabolites in cod were not significantly increased. There was a clear response in micronucleus formation in mussel haemocytes. Other methods that could become useful for monitoring in the future included mixed xenobiotic defence (MXR) components in cod red blood cells, peroxisomal effects in mussel and cellular energy allocation in mussel. No exposure-related effects were seen for glutathione S-transferase in either species or MXR in blue mussel haemocytes. OLF

Traditional mental health studies rely on information primarily collected through personal contact with a health care professional. Recent work has shown the utility of social media data for studying depression, but there have been limited evaluations of other mental health conditions. We consider post traumatic stress disorder (PTSD), a serious condition that affects millions worldwide, with especially high rates in military veterans. We also present a novel method to obtain a PTSD classifier for social media using simple searches of available Twitter data, a significant reduction in training data cost compared to previous work. We demonstrate its utility by examining differences in language use between PTSD and random individuals, building classifiers to separate these two groups and by detecting elevated rates of PTSD at and around U.S. military bases using our classifiers.