She et al. 
Operational Oceanography and Earth System Science 
Frontiers In Earth Science | www.frontlersln.org 
2 
February 2020 | Volume 8 | Article 7 
INTRODUCTION 
Oceanographic monitoring and research has a long history 
in the Baltic Sea. The earliest sea level observations started 
from 1770s (Ekman, 2009). After early German and Swedish 
expeditions in 1871 (“Pommerania” from Kiel) and 1877 
(Swedish expedition by G. Ekman and O. Petterson), the Baltic 
Sea countries Denmark, Finland, Germany, Russia and Sweden 
signed in 1892 a resolution on international cooperation in Baltic 
Sea monitoring and in 1898 an agreement on simultaneous 
investigations on a regular basis at a few selected deep stations in 
the Baltic Sea. With the start of the International Council of the 
Exploration of the Sea (ICES) in 1902 a systematic monitoring 
of the Baltic Sea was established. In the past two decades, 
community coordination of the Baltic Sea oceanography has 
been organized mainly in three areas: marine environment 
monitoring and protection—coordinated by The Baltic Marine 
Environment Protection Commission (HELCOM) since 1992, 
operational oceanography—coordinated by the Baltic Sea 
Operational Oceanographic System (BOOS) since 1998 and 
oceanography research related to climate variability and Baltic 
Sea system science—coordinated by the Baltic Earth program 
(Earth system science for the Baltic Sea region), the successor 
program of the Baltic Sea Experiment (BALTEX) since 1993. 
In addition, fishery monitoring and data management has 
been coordinated by ICES and DG MARE in the Baltic- 
North Sea and European scale, respectively. Due to their 
different mandates, HELCOM members are mainly conducting 
offline, physical-biogeochemical and biological monitoring 
for environment assessment, protection, and ecosystem- 
based management (HELCOM, 2013); BOOS members 
are mainly responsible for online, physical-biogeochemical 
monitoring for operational oceanographic services, e.g., forecast, 
nowcast and hindcast (Buch and Dahlin, 2000; Buch et al., 
2006); ICES members mainly carry out offline monitoring 
ranging from hydrographic to biological parameters for fishery 
management; ICOS (Integrated Carbon Observation System) is 
a European research infrastructure to quantify and understand 
the greenhouse gas balance of the European continent and of 
adjacent regions and is built up as a collaboration of nationally 
operated measurement stations in 12 European countries. 
Most of the monitoring activities in the above categories 
are regular. 
BALTEX/Baltic Earth has a much wider focus. BALTEX was 
founded in 1993 as a network of operational weather services, 
climate centers, and universities with the aim to exchange both 
operational and climate data of the atmosphere, ocean, and land 
surface and to analyze water, energy and matter cycles in the 
Baltic Sea region (Raschke et al., 2001; Omstedt et al., 2004, 2014; 
Reckermann et al., 2011). BALTEX/Baltic Earth is a Regional 
Hydroclimate Project (RHP) within the Global Energy and 
Water Cycle Exchanges Project (GEWEX) of the World Climate 
Research Programme (WRCP). Baltic Earth research aims to fill 
knowledge gaps of the entire regional Earth system (Meier et al., 
2014). However, in this review we limit the discussion mainly to 
the oceanographic component of Baltic Earth following Omstedt 
et al. (2004, 2014). 
Since their establishments, both BALTEX/Baltic Earth and 
BOOS have reached significant achievements in their own 
fields. For operational oceanography, advanced monitoring, and 
forecasting capacities have been developed at local, sub-basin, 
and sea basin scales. Observations and forecasts are shared in 
real or near real time. With sustained observing, the ocean 
state is identified and new phenomena and related knowledge 
are discovered and transferred to the operational hindcast and 
forecast modeling platforms for optimizing existing models; 
by assimilating observations into the operational models, the 
capacity on reconstructing historical and forecasting future 
ocean states is improved. The products generated have been 
used in marine service for blue economy, ocean health, 
and climate change adaptation and mitigation (She, 2018a). 
Currently the BOOS monitoring network provides a significant 
amount of real time observations from e.g., tide gauge stations, 
FerryBox lines, mooring buoys, fixed stations, Argo profilers 
and research vessels (She, 2018b; Siirià et al., 2018). The 
quality of operational ocean-ice-wave-biogeochemical models 
has been significantly improved. Based on the models developed, 
operational forecasting service has been made both in national 
and regional levels (She and Murawski, 2018; Tuomi et al., 2018). 
Data assimilation has been developed to ingrate modeling and 
observations to derive a better initial field for the forecasting 
models and reanalysis for reconstructing the history of the 
Baltic Sea (Zhuang et al., 2011; Fu et al., 2012; Axell, 2013; 
Liu et al., 2017). Major sources for the development of the 
operational oceanography in the Baltic Sea have been the 
Member States. In the past decades, programs from European 
commission, e.g., Operational Oceanography Cluster in the 
Framework Programs 5 and 6 (Cieslikiewicz et al., 2007), 
MyOcean (Bahurel et al., 2010) and following Copernicus 
Marine Environment Monitoring Service (CMEMS) Program 
have strongly supported the integration of Baltic Sea operational 
oceanography in advancing the operational service at the sea 
basin scale. 
Baltic Earth is an independent and open research network 
with the following vision: “Baltic Earth strives to achieve an 
improved Earth System understanding of the Baltic Sea region 
as the basis for science-based management in the face of 
climatic, environmental, and human impact in the region. Baltic 
Earth brings together a broad international research community 
around core scientific issues identified as fundamental to 
informing societal efforts to achieve sustainability in the region. 
These “Grand Challenges (GC)” are tackled through joint 
research efforts, workshops, conferences, and capacity building 
events accompanied by a continuous process of synthesis of the 
current state of knowledge. Communication with stakeholders 
and research funders aims to ensure impact and relevance 
of the research. Baltic Earth targets the atmosphere, land, 
and marine environment of the Baltic Sea, its drainage basin 
and nearby areas with relevance for the Baltic Sea region.” 
(Baltic Earth Science Plan Writing Team, 2017). Following this 
vision, Baltic Earth fosters interdisciplinary and international 
collaboration on processes in the atmosphere, on land and in the 
sea and also in the anthroposphere by organizing conferences, 
workshops, seminars, dedicated sessions at conferences, etc.