el ninio is an event scientists have seen several times but this year's temperatures are quite different. >> what's really different is the water in the north east pacific warmed up over a year ago, usually that warming occurs after the el nino developed but in this case it preceded it. >> ocean warming impacts the food chain from the bottom up. as upwelling winds are causing deep water currents typically rife with cold water nutrients to circulate up mostly nutrient depleted warm water. >> so when you talk about nutrients, what is that? >> that biologic material in the deep ocean gets remineralized to inorganic nutrients and so the upwelling keeps that cycle going. so how does it affect the top of the food chain? the whole food chain gets depressed. a lot of those fish species that could move, have moved northward and the food source is a lot less than we had last year. >> and the evidence can be seen daily all along the california coast from san diego to san francisco. in san diego, sea world, the company which faced public heat for orcha shows, has taken a public role in sea lion resc