Stephan Bojinski

The Concept of Essential Climate Variables in Support of Climate Research, Applications, and Policy

Climate research, monitoring, prediction, and related services rely on accurate observations of the atmosphere, land, and ocean, adequately sampled globally and over sufficiently long time periods. The Global Climate Observing System, set up under the auspices of United Nations organizations and the International Council for Science to help ensure the availability of systematic observations of climate, developed the concept of essential climate variables (ECVs). ECV data records are intended to provide reliable, traceable, observation-based evidence for a range of applications, including monitoring, mitigating, adapting to, and attributing climate changes, as well as the empirical basis required to understand past, current, and possible future climate variability. The ECV concept has been broadly adopted worldwide as the guiding basis for observing climate, including by the United Nations Framework Convention on Climate Change (UNFCCC), WMO, and space agencies operating Earth observation satellites. This ...

Guiding the Creation of A Comprehensive Surface Temperature Resource for Twenty-First-Century Climate Science

Surface temperature data – observed primarily for weather-related purposes – are disparate, originating from ever evolving instrument types and observational practices. Although several global databases are in use internationally, no comprehensive global repository exists and many data are undigitized or restricted. Scientists have painstakingly obtained vast quantities of data, carefully removed random errors and accounted for systematic biases. The 21st Century demands go further - requiring highly detailed (spatially and temporally), globally complete, long-term products, with quantified uncertainties, and created from freely available, fully traceable data. Many decisions of substantial socio-economic importance rely on the accuracy of such products. An international meeting was held to plan how best to facilitate such efforts. A central repository is to be created, where data are traceable from their origins to final product. Strategies are outlined to rescue non-digitized data and move towards entirely freely available data. Creation of multiple methodologically independent products is recommended for quantifying uncertainty. Methods of benchmarking and assessing multiple products to aid inter-comparison and end-user product selection are described. Data-products would be obtained and visualized using in-house tools from the planned data-portal. Structure and governance include engagement with bodies such as WMO and, importantly, with experts other than climatologists.

Reference Upper-Air Observations for Climate: From Concept to Reality

AbstractThe three main objectives of the Global Climate Observing System (GCOS) Reference Upper-Air Network (GRUAN) are to provide long-term high-quality climate records of vertical profiles of selected essential climate variables (ECVs), to constrain and calibrate data from more spatially comprehensive global networks, and to provide measurements for process studies that permit an in-depth understanding of the properties of the atmospheric column. In the five years since the first GRUAN implementation and coordination meeting and the printing of an article (Seidel et al.) in this publication, GRUAN has matured to become a functioning network that provides reference-quality observations to a community of users.This article describes the achievements within GRUAN over the past five years toward making reference-quality observations of upper-air ECVs. Milestones in the evolution of GRUAN are emphasized, including development of rigorous criteria for site certification and assessment, the formal certificatio...

GCOS reference upper air network (GRUAN): Steps towards assuring future climate records

The observational climate record is a cornerstone of our scientific understanding of climate changes and their potential causes. Existing observing networks have been designed largely in support of operational weather forecasting and continue to be run in this mode. Coverage and timeliness are often higher priorities than absolute traceability and accuracy. Changes in instrumentation used in the observing system, as well as in operating procedures, are frequent, rarely adequately documented and their impacts poorly quantified. For monitoring changes in upper-air climate, which is achieved through in-situ soundings and more recently satellites and ground-based remote sensing, the net result has been trend uncertainties as large as, or larger than, the expected emergent signals of climate change. This is more than simply academic with the tropospheric temperature trends issue having been the subject of intense debate, two international assessment reports and several US congressional hearings. For more than a decade the international climate science community has been calling for the instigation of a network of reference quality measurements to reduce uncertainty in our climate monitoring capabilities. This paper provides a brief history of GRUAN developments to date and outlines future plans. Such reference networks can only be achieved and maintained with strong continuing input from the global metrological community.

Recent Advances in Satellite Data Rescue

AbstractTo better understand the impacts of climate change, environmental monitoring capabilities must be enhanced by deploying additional and more accurate satellite- and ground-based (including in situ) sensors. In addition, reanalysis of observations collected decades ago but long forgotten can unlock precious information about the recent past. Historical, in situ observations mainly cover densely inhabited areas and frequently traveled routes. In contrast, large selections of early meteorological satellite data, waiting to be exploited today, provide information about remote areas unavailable from any other source. When initially collected, these satellite data posed great challenges to transmission and archiving facilities. As a result, data access was limited to the main teams of scientific investigators associated with the instruments. As archive media have aged, so have the mission scientists and other pioneers of satellite meteorology, who sometimes retired in possession of unique and unpublished...

Prioritizing Global Observations Along Essential Climate Variables

The Global Climate Observing System (GCOS) Secretariat, housed within the World Meteorological Organization, released in August 2010 updated guidance for priority actions worldwide in support of observations of GCOS Essential Climate Variables (ECVs). This guidance states that full achievement of the recommendations in the 2010 Implementation Plan for the Global Observing System for Climate in Support of the UNFCCC (http://www.wmo.int/pages/prog/gcos/Publications/gcos-138.pdf) is required to ensure that countries are able to understand and predict climate change and its impacts and manage their response throughout the 21st century and beyond. GCOS is sponsored by the United Nations and the International Council for Science (ICSU) and is an internationally coordinated network of observing systems and a program of activities that support and improve the network, which is designed to meet evolving national and international requirements for climate observations. One of the main objectives of GCOS is to sustain observations into the future to allow evaluation of how climate is changing, so that informed decisions can be made on prevention, mitigation, and adaptation strategies. GCOS priorities are based on the belief that observations are crucial to supporting the research needed to refine understanding of the climate system and its changes, to initialize predictions on time scales out to decades, and to develop the models used to make these predictions and longer-term scenario-based projections. Observations are also needed to assess social and economic vulnerabilities and to support related actions needed across a broad range of societal sectors by underpinning emerging climate services.

Developing Strategies for Future Climate Change Science: Future Climate Change Research and Observations: GCOS, WCRP and IGBP Learning From the IPCC Fourth Assessment Report; Sydney, Australia, 4–6 October 2007

Learning from the findings of the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report to design future strategies for climate change research and observations was the key objective of a workshop organized jointly by the Global Climate Observing System (GCOS), the World Climate Research Program (WCRP), and the International Geosphere- Biosphere Programme (IGBP) in Sydney, Australia. Some 66 key IPCC authors and other experts associated with the three international programs discussed ways to sustain and develop future observing systems and to define climate change research challenges, based on gaps and uncertainties identified by IPCC Working Group I (The Physical Science Basis) and Working Group II (Impacts, Adaptation, and Vulnerability) in their latest assessments.