repairs a broken navigation module in Greenland.© 2 0 1 9 S p r i n g e r N a t u r e L i m i t e d . A l l r i g h t s r e s e r v e d . A researcher accesses sediment cores collected during an ocean-drilling programme.MARC STEINME TZ/VISUM/EYEVINE 6 J U N E 2 0 1 9 | V O L 5 7 0 | N A T U R E | 2 9 COMMENT © 2 0 1 9 S p r i n g e r N a t u r e L i m i t e d . A l l r i g h t s r e s e r v e d .

A research agenda for intelligent systems that will result in fundamental new capabilities for understanding the Earth system.

Scientific researchers today frequently package measurements and associated metadata as digital datasets in anticipation of storage in data repositories. Through the lens of environmental data stewardship, we consider the data repository as an organizational element central to data curation. One aspect of non-commercial repositories, their distance-from-origin of the data, is explored in terms of near and remote categories. Three idealized repository types are distinguished – local, center, and archive - paralleling research, resource, and reference collection categories respectively. Repository type characteristics such as scope, structure, and goals are discussed. Repository similarities in terms of roles, activities and responsibilities are also examined. Data stewardship is related to care of research data and responsible scientific communication supported by an infrastructure that coordinates curation activities; data curation is defined as a set of repeated and repeatable activities focusing on tending data and creating data products within a particular arena. The concept of “sphere-of-context” is introduced as an aid to distinguishing repository types. Conceptualizing a “web-of-repositories” accommodates a variety of repository types and represents an ecologically inclusive approach to data curation.

Antarctic phytoplankton is characterized by a pronounced seasonality in abundance, driven mainly by changes in sunlight. We combined measurements and modeling to describe the influence of changing daylength on fall and winter phytoplankton production in coastal waters of the western Antarctic Peninsula (wAP) in 2001 and 2002. The model was parameterized with field observations from the Palmer Long-Term Ecological program in the wAP during summer and early fall and from the Southern Ocean Global Ecosystems Dynamics program fall and winter cruises to Marguerite Bay and shelf waters. Shorter daylength and a deepening of the mixed layer account for most of the decrease in primary production during March, April, and May. At this time, biomass decreases by an order of magnitude and remains low and constant until the end of August. An additional loss rate was added to the primary production model to fit output to observations. This loss rate, estimated at ~0.1 to 0.15 d −1 , is due to physical, chemical, and biological processes such as scavenging by sea ice, zooplankton grazing, cell lysis, and cell sedimentation, which are expected to be high at this time of year. Growth and loss rates of phytoplankton populations are similar on 1 March, with growth decreasing rapidly over time while the loss rates remain constant. By the beginning of winter (1 June), growth is low, with minimum rates in July and increasing towards September. During a period of diminishing food supply, preliminary estimates of grazing indicate that fall biomass could support existing macrozooplankton populations, but the timing and concentration of food supply is variable and expected to affect health of zooplankton as they enter the winter.KEY WORDS: Phytoplankton · Primary production · Antarctica · Bloom demise · Fall · Winter · Growth rates · Loss rates Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 452: [45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61] 2012 summer of 1 to 3 mg chlorophyll a (chl a) m −3 with peaks or blooms up to 30 mg m −3 (Smith et al. 1998) decreases to a low of < 0.2 mg m −3 in the winter , Fritsen et al. 2008, Meyer et al. 2009). In the fall, phytoplankton biomass is variable, with chl a concentrations anywhere from 0.1 to 2 mg m −3 within the surface mixed layer (Vernet et al. 2011).Our knowledge of fall and winter phytoplankton dynamics in the Southern Ocean is limited by the difficulty of sampling underneath the ice and the lack of ocean color remote sensing images from April to October due to low sun angle (Marrari et al. 2008). This lack of information precludes understanding variability due to latitude and interannual changes in the water column. Scarce supply of food during winter combined with low starvation tolerance of some zooplankton, e.g. larval krill, might necessitate their use of an alternative food source (Walsh et al. 2001). Several investigators (Daly 1990, Smetacek et al. 1990, Quetin & Ross 1991 have suggested that sea i...

In contemporary scientific research, standard-making and standardization are key processes for the sharing and reuse of data. The goals of this paper are twofold: 1) to stress that collaboration is crucial to standard-making, and 2) to urge recognition of metadata standardization as part of the scientific process. To achieve these goals, a participatory framework for developing and implementing scientific metadata standards is presented. We highlight the need for ongoing, open dialogue within and among research communities at multiple levels. Using the Long Term Ecological Research network adoption of the Ecological Metadata Language as a case example in the natural sciences, we illustrate how a participatory framework addresses the need for active coordination of the evolution of scientific metadata standards. The participatory framework is contrasted with a hierarchical framework to underscore how the development of scientific standards is a dynamic and continuing process. The roles played by ‘best practices’ and ‘working standards’ are identified in relation to the process of standardization.