This dataset is from the Northern Ireland (NI) DELTA® Gas and Aerosol Monitoring Network, and consists of monthly atmospheric concentrations of inorganic, water-soluble, reactive gases and aerosols measured with the UKCEH DELTA® method at 4 sites across NI for the years 2019 to 2020. • Gases: ammonia (NH3), nitric acid (HNO3), sulphur dioxide (SO2) • Aerosols: ammonium (NH4+), nitrate (NO3-), sulphate (SO42-), chloride (Cl-), sodium (Na+), calcium (Ca2+), Magnesium (Mg2+) The network is operated jointly by Agri-Food and Biosciences Institute (AFBI) and the UK Centre for Ecology & Hydrology (UKCEH), and funded by the Department of Agriculture, Environment and Rural Affairs (DAERA), Northern Ireland. Full details about this dataset can be found at https://doi.org/10.5285/55ad7cf8-fc40-4b8a-9d35-ce970a915ff6

This dataset provides weekly pollutant concentration and deposition data in cloud and rain samples from the, now retired, Bowbeat field site near Edinburgh, UK. The data were captured approximately weekly between 03/09/2003 and 28/06/2006 using a cloud droplet collector and rainwater collector. They were collected to monitor and model cloud/rain water composition and deposition at high elevation as part of ongoing routine measurements. Full details about this dataset can be found at https://doi.org/10.5285/2dca8f2f-a21b-4f77-bc8c-326269ab58d1

This dataset contains results from in situ field measurements of riverbed nitrogen transformations in the Hammer Stream, a sandy tributary of the River Rother in West Sussex, UK. Measurements were performed in November 2014 and February, April and July 2015. The data include baseline concentrations of nutrients (NO2, NO3, NH3, PO4), chloride, oxygen, pH, temperature, Fe(II), organic carbon, 15N-N2 and methane (CH4) and nitrous oxide (N2O) sampled from porewater prior to injection of 15N-nitrate. Full details about this dataset can be found at https://doi.org/10.5285/7ded510f-3955-4b92-851d-29c0f79a0b99

This dataset contains nutrient chemistry data from 14 lakes in the Arctic region: 4 in Russia and Alaska and 3 in Greenland and Norway. Nutrient chemistry was measured on one occasion only at each lake, with date of collection ranging from 01/04/2011 to 14/03/2014. The following nutrients were measured: total phosphorus, soluble reactive phosphorus, total nitrogen, nitrate, ammonium, chlorophyll a, silicate, sodium, magnesium, potassium, calcium, sulphate, chloride and dissolved organic carbon. All nutrients were measured using standardised methods and the same methods were used between lake samples. The data were collected as part of the Lakes and the Arctic Carbon Cycle (LAC) project, which is funded under NERC's Arctic Research Programme. Full details about this dataset can be found at https://doi.org/10.5285/b6f1e1a4-1f3b-4b74-99e5-651ade10f32c

The dataset contains concentrations of Total Organic Carbon, Chloride, Fluoride, Bromine, Sulfate, Potassium, Aluminium, Calcium, Iron, Magnesium, Sodium, Phosphorus, Chromium, Manganese, Cobalt, Nickel, Copper, Zinc, Arsenic, Selenium, Molybdenum, Cadmium, Lead and stable water isotopes (δD and δ18O) for 25 groundwater and surface water sampling locations, surveyed over the period February 2017 to May 2018 immediately following Dineo floods. The data were collected as part of the PULA project, which aimed at understanding the immediate effect of heavy rainfall and floods on water resources in arid Botswana and their transitional hydrologic readjustment towards the dry period, and the role of these events in supporting either or both resources replenishment and contamination. The project was co-ordinated by the University of Aberdeen, with partners at the Botswana International University of Science and Technology, the Government of Botswana Department of Water Affairs, and the International Water Management Institute. The project was funded by the Natural Environment Research Council as part of its Urgency grants scheme. Full details about this dataset can be found at https://doi.org/10.5285/c7793128-1961-45d5-aa18-5f023116784b

Discrete data for major ions and nutrients in river water for 13 sites in the Humber catchment over the periods 1993 to 1997 and 1996 to 1997 and for 3 sites from the Tweed catchment over the period 1994 to 1997. Ions and nutrients measured were: Ammonia, Calcium (dissolved), Magnesium (dissolved), Potassium (dissolved), Sodium (dissolved), Bromide-ion, Carbon (organic dissolved), Chloride-ion, Nitrate, Nitrite, Phosphorus (soluble reactive), Phosphorus (total dissolved), Silicate (reactive dissolved), Sulphate, Carbon (organic particulate), Nitrogen (particulate), Phosphorus (total). Sites were sampled at regular weekly intervals and more intermittently during high flows (on average an extra sampling once a month per site). Samples were obtained using a wide neck PTFE bottle in a plastic covered bottle carrier (lowered from bridges where possible otherwise collected by immersing sample bottle by hand in the water as near the main flow as possible). Samples were filtered through Whatman 0.45um sterile membrane filters immediately on return to laboratory. Samples stored in sterilin tubes in the dark at 40C and analysed by Dionex DX100 ion chromatography system. Silicate reactive dissolved and Chloride-ion concentrations were determined by automated colourimetry and dissolved organic carbon concentrations were determined using a TOCsin II aqueous carbon analyser. Some samples on the River Aire were collected using EPIC automatic samplers. The analysis was carried out by members of the analytical chemistry section at York University (from April 1994 until November 1996) and at Wallingford Institute of Hydrology (September 1993 to April 1994 and December 1996 to April 1997), as part of the Land Ocean Interaction Study (LOIS). Full details about this dataset can be found at https://doi.org/10.5285/4482fa14-aee2-4c7f-9c62-a08dc9704051

Chemical composition of freshwater samples from sites in Northern England. Measurements of pH, dissolved major ions (Na, Mg, K, Ca, Cl, NO3, SO4), dissolved organic carbon (DOC), dissolved Al, Fe(II) and total Fe, and measurements of Al, Fe(II) and total Fe on samples following dialysis.

Precipitation chemistry data from the UK Environmental Change Network (ECN) terrestrial sites. Variables measured include pH, conductivity, alkalinity, aluminium, calcium, chloride, ammonium, nitrate nitrogen, phosphate phosphorous, potassium, sulphate sulphur, sodium, total nitrogen and total dissolved phosphorous. These data are collected by a bulk collector at all of ECN's terrestrial sites using a standard protocol. They represent continuous weekly records from 1992 to 2015. ECN is the UK's long-term environmental monitoring programme. It is a multi-agency programme sponsored by a consortium of fourteen government departments and agencies. These organisations contribute to the programme through funding either site monitoring and/or network co-ordination activities. These organisations are: Agri-Food and Biosciences Institute, Biotechnology and Biological Sciences Research Council, Cyfoeth Naturiol Cymru - Natural Resources Wales, Defence Science & Technology Laboratory, Department for Environment, Food and Rural Affairs, Environment Agency, Forestry Commission, Llywodraeth Cymru - Welsh Government, Natural England, Natural Environment Research Council, Northern Ireland Environment Agency, Scottish Environment Protection Agency, Scottish Government and Scottish Natural Heritage. Full details about this dataset can be found at https://doi.org/10.5285/18b7c387-037d-4949-98bc-e8db5ef4264c

[THIS DATASET HAS BEEN WITHDRAWN]. Stream water chemistry data from the UK Environmental Change Network (ECN) terrestrial sites. Variables measured include pH, conductivity, alkalinity, aluminium, calcium, chloride, ammonium, nitrate nitrogen, phosphate phosphorous, potassium, sulphate sulphur, sodium, total nitrogen and total dissolved phosphorous. The data are collected by dip samples at ECN's terrestrial sites (where there is a stream present) using a standard protocol. They represent continuous weekly records from 1992 to 2012. The sites at which these data are collected are: Cairngorms, Glensaugh, Moor House-Upper Teesdale, North Wyke, Rothamsted, Sourhope, Wytham and Y Wyddfa (Snowdon). ECN is the UK's long-term environmental monitoring programme. It is a multi-agency programme sponsored by a consortium of fourteen government departments and agencies. These organisations contribute to the programme through funding either site monitoring and/or network co-ordination activities. These organisations are: Agri-Food and Biosciences Institute, Biotechnology and Biological Sciences Research Council, Cyfoeth Naturiol Cymru - Natural Resources Wales, Defence Science & Technology Laboratory, Department for Environment, Food and Rural Affairs, Environment Agency, Forestry Commission, Llywodraeth Cymru - Welsh Government, Natural England, Natural Environment Research Council, Northern Ireland Environment Agency, Scottish Environment Protection Agency, Scottish Government and Scottish Natural Heritage. Full details about this dataset can be found at https://doi.org/10.5285/5a715fd9-aefa-40cc-bbb6-56984b6db554

Stream water chemistry data from the UK Environmental Change Network (ECN) terrestrial sites. Variables measured include pH, conductivity, alkalinity, aluminium, calcium, chloride, ammonium, nitrate nitrogen, phosphate phosphorous, potassium, sulphate sulphur, sodium, total nitrogen and total dissolved phosphorous. The data are collected by dip samples at ECN's terrestrial sites (where there is a stream present) using a standard protocol. They represent continuous weekly records from 1992 to 2015. The sites at which these data are collected are: Cairngorms, Glensaugh, Moor House - Upper Teesdale, North Wyke, Rothamsted, Sourhope, Wytham and Y Wyddfa (Snowdon). ECN is the UK's long-term environmental monitoring programme. It is a multi-agency programme sponsored by a consortium of fourteen government departments and agencies. These organisations contribute to the programme through funding either site monitoring and/or network co-ordination activities. These organisations are: Agri-Food and Biosciences Institute, Biotechnology and Biological Sciences Research Council, Cyfoeth Naturiol Cymru - Natural Resources Wales, Defence Science & Technology Laboratory, Department for Environment, Food and Rural Affairs, Environment Agency, Forestry Commission, Llywodraeth Cymru - Welsh Government, Natural England, Natural Environment Research Council, Northern Ireland Environment Agency, Scottish Environment Protection Agency, Scottish Government and Scottish Natural Heritage. Full details about this dataset can be found at https://doi.org/10.5285/fd7ca5ef-460a-463c-ad2b-5ad48bb4e22e