Bring a pot of salted water to a boil and cook the whole wheat fettuccine according to package directions until al dente.
While pasta cooks, season the salmon fillet with half of the sea salt and black pepper.
Heat a non-stick skillet over medium-high heat and sear the salmon for 4-5 minutes per side until flaky and golden.
Remove salmon from the pan, let it rest for 2 minutes, then gently flake it into large bite-sized pieces.
In the same skillet, add the trimmed asparagus spears with a splash of water, covering for 2 minutes until crisp-tender.
In a small bowl, whisk together the Greek yogurt, lemon juice, lemon zest, garlic powder, and remaining salt and pepper.
Drain the pasta, reserving 2 tablespoons of pasta water, and return the pasta to the pot.
Stir in the yogurt mixture, reserved pasta water, asparagus, and fresh dill until the noodles are well coated.
Fold in the flaked salmon gently and serve immediately.