DOI: 10.5061/dryad.6djh9w17t
title: Data for: Land use change and coastal water darkening drive synchronous dynamics in phytoplankton and fish phenology on centennial time scales

description: At high latitudes, the suitable window for timing reproductive events is
 particularly narrow, promoting tight synchrony between trophic levels.
 Climate change may disrupt this synchrony due to diverging responses to
 temperature between e.g. the early life stages of higher trophic levels
 and their food resources. Evidence for this is equivocal, and the role of
 compensatory mechanisms are poorly understood. Here, we show how a
 combination of ocean warming and coastal water darkening drive long-term
 changes in phytoplankton spring bloom timing in Lofoten Norway, and how
 spawning time of Northeast Arctic cod responds in synchrony. Spring bloom
 timing was derived from hydrographical observations dating back to 1936,
 while cod spawning time was estimated from weekly fisheries catch and roe
 landing data since 1877. Our results suggest that land use change causing
 coastal water darkening has gradually delayed the spring bloom up to 1990
 after which ocean warming has caused it to advance. The cod appear to
 track phytoplankton dynamics by timing gonadal development and spawning to
 maximize overlap between offspring hatch date and predicted resource
 availability. This finding emphasises the importance of land-ocean
 coupling for coastal ecosystem functioning, and the potential for fish to
 adapt through phenotypic plasticity.
description: <strong>Andenes surface
 temperature</strong> The monthly mean sea surface
 temperature (C°) from the Andenes lighthouse (69.3 °N, 16.1 °E) for the
 years 1868 to 1963 where drawn from two sources.  
 For the period 1868-1945, temperatures where drawn directly from
 the  publication <em>Means and extremes of sea temperature by the
 Norwegian coast </em>tables 291a and 291b (pages 61-62)  by E.
 Frogner (1948, Geofysiske publikasjoner Vol. XV Issue 3 Pages 5-74). The
 raw data consisted of 8-hourly to daily observations, but are processed to
 monthly means by E: Frogner, without uncertainty. The wherabouts of the
 raw data is unknown. For the period 1946-1963,
 monthly mean temperatures where made available upon request to the The
 Norwegian Meteorological Institute (www.met.no).  
 <strong>NEA cod catch statistics
 1877-2021</strong> Weekly resolved commercial
 landings of NEA cod and NEA cod-roe between 1877 and 2022 were drawn from
 the Official Fisheries Statistics of Norway via two pathways. 
 For the period 1877 to 2014 these recordnings are available both
 as printed books and scanned copies available at a digital repository managed by the Norwegian Directorate of Fisheries. The name of the report, the report-series and the publisher changes through the years, and include the following titles.  1863-1878: Om Lofotfiskeriet aar [year], Årsberetning vedkommende Norges fiskerier,Departement for det indre 1879-1899: Lofotfiskeriet [year], Årsberetning vedkommende Norges fiskerier, Departement for det indre 1900-1905: Lofotfiskeriet [year], Årsberetning vedkommende Norges fiskerier, Norges fiskeristyrelse 1906-1922: Lofotfiskeriet [year], Årsberetning vedkommende Norges fiskerier, Fiskeridirektøren 1923-2000: Lofotfisket [year], Årsberetning vedkommende Norges fiskerier, Fiskeridirektøren 2001-2014: Melding fra utvalgsformannen for Lofotfisket. Meldingsåret [year], Årsberetning vedkommende Norges fiskerier, Fiskeridirektoratet For a partly overlapping period 2000-2022 these data have been digitized and made available by the Norwegian Directorate of fisheries at this website, described in Hopland & Aasheim (2023). <strong>Litterature</strong> The publication by E. Frogner (1948) and the data documentation for the 2000-2022 catsch statistics by Hopland & Aasheim (2023) have also been uploaded. 
description: **File: Surface_Temp_Andenes_1868_1963.txt** This file describes the
 monthly mean surface temperature at the Andenes lighthouse, Norway (69.3
 °N, 16.1 °E) in the period 1968 to 1963. Temperaure: degrees Celcius (NaN
 = not a number) Colunmns #1; year Columns #2-13: months Jan-Dec. **File:
 Fish_landings_1877_2022.txt** This file describes the weekly
 catches/landings of Northeast Arctic (NEA) cod in Lofoten, Norway, in the
 period 1877-2022 Landed fish: tonnes (1000 kg) gutted NEA cod (NaN = not a
 number) Column #1: year Column #2-20: Week number. Week #1 is the first
 week of the year **File: Roe_Landings_1877_2022.txt** This files describes
 the weekly landings of Northeast Arctic (NEA) cod roe in Lofoten, Norway,
 in the period 1877-2022. This dataset is directly linked to the above
 dataset on NEA cod landings, as the landed roe quantity is extracted from
 the landed cod. Landed roe: tonnes (1000 kg) NEA cod roe (NaN = not a
 number) Column #1: year Column #2-20: Week number. Week #1 is the first
 week of the year