Coral reef ecosystems are exposed to a diverse suite of environmental forcing. Waves, wind, currents, temperature, irradiance, salinity, nutrients, turbidity, aragonite saturation state, and planktonic productivity each influence coral reefs to varying degrees, fluctuating on daily, seasonal and interannual time scales and across spatial scales spanning reefs, islands and archipelagos [1-3]. Environmental forcing is highly influential to reef ecosystem process and function, including coral reef extent and growth rates and the abundance, diversity, and morphology of reef organisms [1, 4]. Through time, coral reef ecosystems have adapted to exist within a particular climatological setting; a finite range in long-term physical, chemical and biological environmental forcing that is region specific and governed by a reef’s geographic location [2]. Regional variability (100s-1000s of kilometers) in the climatological setting is a major determinant for spatial differences in coral reef ecosystems [3]. Environmental forcing that exceeds the climatological setting can be considered beyond a reef ecosystem’s ‘normal’ or adapted range of environmental conditions [1]. For example, ENSO related forcing can drive variations in ocean temperatures, salinity, and ocean waves not observed on a reef ecosystem for years to decades. Depending on the magnitude and duration of exceedance forcing, considerable ecological consequences to coral reef ecosystem can result [5-7]. In recent decades it has become abundantly clear that coral reef communities are not only structured by natural environmental forcing, but also by human related activities [8]. Local human impacts include habitat and water quality degradation associated with land clearing, improper waste water treatment, and coastal urbanization [9, 10], as well as destructive and over fishing practices [11-13]. In addition, human-induced climate change is driving global-scale changes in environmental forcing, including ocean warming, ocean acidification, sea-level rise, and increased storminess, each of which have profound implications to the future of coral reef ecosystems [1, 8, 14-17]. Coral reefs are among the most diverse and productive marine ecosystems on earth and provide economic benefits to millions of people as sources of food, employment, natural products, coastal protection and recreation [17, 18]. Despite this societal importance, the interplay between coral reef ecosystem dynamics and the environmental conditions in which they exist are not fully understood. Further confounding this knowledge-gap is our ability to discern human versus natural induced perturbations in reef ecosystem health, which can act synergistically and be difficult to ascertain [1]. Now, more than any other time in our history, effective ecosystem-based management and successful strategies to mitigate anthropogenic impacts to coral reef ecosystems require proper characterization of environmental conditions to help assess the underlying abiotic-biotic interactions determining coral reef ecosystem function and health. CRED has provided climatological and time series information for the following parameters to characterize environmental conditions on coral reef ecosystems across the Pacific; wind, waves, sea surface temperature (SST), chlorophyll-a, irradiance, sea surface height, ocean currents, dissolved inorganic carbon (DIC), total alkalinity (TA) and precipitation. These environmental parameters were chosen as they represent the primary drivers of coral reef ecosystem variability (through space and time) and/or serve as a proxy for other pertinent environmental variables to reef ecosystems. Ideally, additional environmental parameters would be included (e.g. salinity, dissolved inorganic nutrients, etc) to provide a more comprehensive assessment of environmental conditions; however, there are limits to the availability of science-quality information at the appropriate spatial and temporal resolution required for climatological and time series calculations.