National Oceanic and Atmospheric Administration
UNITED STATES DEPARTMENT OF COMMERCE
The Under Secretary of Commerce for Oceans and Atmosphere
Washington. D.C. 20230
October 7, 2010
Dear Senator Bob Graham and the Honorable William K. Reilly, co-chairs National Commission on the BP Deepwater Horizon
Oil Spill and Offshore Drilling
The BP oil spill was an unprecedented and dynamic event. It continues to require serious attention to every aspect of the federal oil spill response, damage assessment and restoration activities. We must do all we can to learn from this experience to prevent such a spill from occurring again and incorporate lessons learned in the event it does. I thank you for your efforts toward those ends.
Under federal law, NOAA is the nation’s lead science agency for oil spills in the coastal and marine environment. From the earliest hours of this event, our job has been to use the best science to create the tools responders need to make on-the-ground decisions in real-time during the crisis. We also take seriously the President’s commitment to science, openness and transparency, and have consistently attempted to share information with the public as soon as we were confident it was accurate.
NOAA will provide more detailed comments to the commission’s draft Staff Working Paper issued yesterday, but I write to alert you to a mischaracterization of NOAA’s document entitled ‘Modeling the Potential Long Term Movement of Oil’ in the draft Staff Working Paper Number 3 entitled ‘Amount and Fate of the Oil’. The draft Staff Working Paper says, “The Commission staff has also been advised that, in late April or early May 2010, NOAA wanted to make public some of its long-term, worst-case discharge models for the Deepwater Horizon spill, and requested approval to do so from the White House’s Office of Management and Budget. Staff was told that the Office of Management and Budget denied NOAA’s request.” Specifically, I wish to set the record straight on three fronts.
1. NOAA’s modeling of long-term movement of oil using worst-case scenario analyses was completely independent of the efforts to estimate flow rate. They are different. ‘Worst-case scenario modeling’ was designed to evaluate where oil might go over time and is not the same as ‘worst-case discharge.’ The sentences from the draft Staff Working Paper (above) imply they are the same, and are thus misleading.
You’ll recall that NOAA was issuing twice a day short-term trajectories of oil movement to inform day-to-day responses. Those models began with daily-updated distributions of surface oil and short-term forecasts for weather and ocean currents to forecast oil movement up to 72 hours out.
The Unified Command was also interested in having longer term projections of possible oil movement. In response, NOAA ran a completely different series of models for possible worst-case scenarios, using oceanographic models of the Gulf and historical information about behavior of currents and weather for that time of year (vs. the actual conditions and short-term forecasts). The model runs used a range of possible daily flow rates, for example ranging from 5,000 to 50,000 barrels per day, where oil was assumed to flow for 90 days and the models forecast where oil would end up after 120 days. Hence, these models used various flow rates as input to forecast movement, but were entirely separate from the efforts to calculate flow rate.
2. The document suggests that the early low flow rate estimates might have hampered the federal response. This was not the case. Two goals of the worst-case scenario modeling were to inform the Unified Command’s understanding about possible scenarios and aid the response effort, both of which happened.
3. NOAA also wanted to share the outcome of these models with the public, and so prepared a short description of the models and outcomes and submitted the document through OMB’s interagency clearance process. Due to the complexity of the models, the challenges of accurately but clearly communicating to non-technical audiences what they said, and the dynamic nature of the event coupled with the desire to have the product be as current as possible, the work took some time. I believe the end product was consistent with the highest professional standards and best available scientific data. Contrary to suggestions in the Draft Staff Working Paper, the document was cleared and released to the public.
In summary, the worst-case scenario models and documents had nothing to do with calculation of the flow rate, but they did help inform the Unified Command’s preparations for possible eventualities. And the worst-case scenario paper was made public.
NOAA fully supports the commission’s efforts to learn as much as we can from this event. This includes ways to better communicate information to the public during a response. Throughout this event, I and all of NOAA have been committed to being as transparent and forthcoming with information as possible, while also ensuring that the best science underpin all that we do. We look forward to working with you and your staff.