There are a few comics with Katara writing her diary. Let's think that this is an abstract from it...
Your eyes are colored like wind
The Wind from the northern sea...
Aquarium
His eyes. They are just like him. Stormy clouds, hiding the sun. They are constantly changing their tint, becoming either almost transparent or quite impenetrable like a storm veil. They reflect fire and become brown. And when he looks at the ocean, they absorb a thousand shades of ocean waves. On a clear day they sparkle like blue topazes, which can pacify the gale as an ancient belief says. And I little more, his eyes are gray granite and steel, and only I know how stubborn and determined he can be. "The water wears stone away," people say. Water doesn't feel any easier about that, believe me. I catch his eye, and my heart turns into a red hot air balloon of Fire Nation - it rises higher, gets stuck in my throat, hinder breathing, sear my cheeks with heat. To find a distraction, I search for a comparison that would describe his eyes. But I can not - and I feel dizzy.
His eyes are his self. He seems to be a young boy whose thoughts can be easily read on his face as the clouds running in the sky can be seen in his gray eyes. He does feel like a boy: he doesn't trust his power, dislikes responsibility, doesn't want to be serious. But sometimes, meeting his glance, I'm lost. Just as long ago standing on my knees on the edge of the ice and trying to see the depths where penguins vanish, chasing fish. His eyes seem as impenetrable for my gaze, as the ocean waters. As the times when there was no war are incomprehensible for my mind. But he was born there and then. He spent his childhood in the depths of peace time. He's one hundred and twelve. He saw the world as it will never be again. He knows things that I won't ever perceive even if he tells me. I catch his boyish grin, trying not to think about it. But I can not - and I feel dizzy.
His eyes. I don't know what color were the eyes of the Air Nomads, nobody in my world does. I don't know from whom – from his mother or from his father – he inherited this unpredictable storm tint. But the worst thing to me is when this gray depth is pierced with the rays of otherworldly light which forces it out of his eyes. Because at that moment he no longer belongs to the world - neither the one it is now, nor the one it was during his childhood. I can't catch his eye, I see no fire, no waves, no sky in it, but a blinding light, in which there is no place for me. I can't catch his smile, because his face becomes an impassive mask, behind which there is no room for the boy Aang. I do not want to remember that the one, whose confused glance and embarrassed smile I catch sometimes, is the most powerful being in the universe. But I can not - and I feel dizzy.
His eyes... They are just like what they must be because they are him. Gusty like a whirlwind. Playful as a sea breeze. Unfathomable as the ocean. Firm as gray granite. Catching like flame. But my eyes are also my essence. Water. Water extinguishes any flame, absorbs it without any harm to itself. It turns rough granite to smooth pebbles, with which children play on the shore, and drowns entire continents in its depths. But only the air is able to procreate life in it. And only the gale makes waves storm and the sea rampage. And only the wind is able to calm and subdue them.