In just two months, Shell Oil could do in America’s Arctic Ocean what British Petroleum has done in the Gulf of Mexico—drill an environmental time bomb without being able to defuse it or deal with the consequences of it going off.

In both cases, we’re talking about exploratory offshore oil drilling under conditions so extreme that the risks are unreasonable and the consequences severe.

For gulf coast residents, the impact of BP’s exploratory oil drilling explosion is tragic: 11 drill workers lost their lives, fishermen are losing their livelihoods, and the impacts are increasing daily. Two weeks later, the environmental consequences are building offshore in an oil mass the size of Puerto Rico. Growing daily by more than 200,000 gallons, the oil is killing sea birds and attacking the habitat of more than 400 animal species. It threatens four coastal states and could become—in the words of President Barack Obama—an unprecedented environmental and economic disaster.

We can’t afford to witness another such disaster in the Arctic, where exploratory drilling has been greenlighted by the Obama administration and could begin as early as July 1.

Other than a court order – which we are seeking – only President Obama can stop Shell at this point, and he should base his re-consideration on the chilling parallels between these two drilling scenarios.

Shell convinced the federal Minerals Management Service that any risk associated with exploratory drilling in the Beaufort and Chukchi seas is small and can be dealt with. Sound familiar? It’s what BP told authorities just a year before the Gulf blowout – that "the probability of a large spill occurring during exploration is insignificant." The company didn’t even have a contingency plan for a blowout.

MMS said it did not consider the possible impacts of a "large" or "very large" oil spill when it approved Shell’s drilling permit. MMS quantifies a large spill as being between 1,000 and 149,999 barrels of oil; they quantify a very large spill as being greater than 150,000 barrels of oil. By comparison, the BP spill is pouring out at least 5,000 barrels a day, which many sources believe is an underestimate, and some predict it will eclipse the 11-million-gallon Exxon-Valdez spill.

MMS’ unreasonable—and we think illegal—failure to consider the potential of a major spill, and the inability of Shell, or any oil company, to clean up an oil spill in the Arctic Ocean’s icy waters is why we are going to the 9th Circuit Court in Portland on Thursday. We are defending 13 conservation groups and Alaska Natives who would be devastated by an oil spill in these fragile waters.

Just as the Gulf is home to hundreds of animal species—including endangered turtles and tuna—the Arctic waters where Shell aims to drill are also home to endangered and threatened species, including bowhead whales, polar bears and spectacled and Steller’s eiders. Similar to the Gulf Coast where generations of residents have depended on its riches for their livelihood and subsistence, Native communities across Alaska’s North Slope rely heavily on fish and wildlife from the Arctic Ocean for their survival.

This remote region is the least understood area of our oceans. It presents challenges not faced in the Gulf, including frigid temperatures and ice-clogged seas. President Obama should direct his administration to hold off on drilling in the Arctic Ocean this summer and instead take a cautious, science-based approach to determine how best to proceed in this fragile, complex ecosystem.

Ultimately, the only way to keep oil spills from harming our nation’s people and wildlife is to end our dependence on oil itself. We need to depend on our own American ingenuity—to develop clean, alternative sources of energy like wind, solar, hydrogen, and biofuels.