Preheat the oven to 400ºF and adjust the rack to the middle position. Place the salmon on a baking dish lined with parchment paper. Sprinkle with Celtic Sea salt. Place the salmon in the oven and roast for 11 minutes.
Meanwhile, place the parsley, cilantro, garlic, and sea salt in a food processor and pulse until coarsely chopped, about 5 one-second pulses. Add the olive oil and vinegar and pulse, until combined, about 5 one-second pulses. Transfer to bowl; set aside.
Spoon the chimichurri over top of each salmon fillet and serve.