Climate Departure: Oceans already outside historical variability as cities and ecosystems follow

Researchers from the University of Hawaii have estimated the year when we depart the climate variability we have historically known for cities around the globe. But the study also identifies that the planet's oceans have already passed their climate departure point, and that the greatest impact of global warming will be felt in biodiversity and ecosystems in the tropics.

In a study published in Nature - The projected timing of climate departure from recent variability (abstract) - researchers lead by Camilo Mora from the Geography Department at the University of Hawaii sought to identify the point at which the climate at 54,000 locations on Earth will exceed the bounds of historical variability. They used a baseline period of 1860 to 2005 to determine natural temperature variability. Using results averaged from 39 different climate models, they then determined for each location measured the year point in which the coldest years are likely to be consistently hotter than any of the past 150 years.

Tropical insects face catastrophic reduction in reproduction with climate change

It looks like cold blooded species (ectotherms) in the tropics could be at an extreme risk of extinction with just moderate increases in temperature according to scientific studies. The latest study looked at the effects of increased temperature on the entire life cycle of one tropical ectotherm species, suggesting reproduction may suffer a catastrophic reduction as the climate warms with just moderate increases in tropical temperatures. The research has possible ramifications for all tropical ectotherms - Insects, spiders, frogs, snakes, turtles and other reptiles.

This is not the first indication that global warming impact on tropical species is greater than expected. Small increases in temperature in tropical ecosystems can have large impacts as many species are already near their thermal physiological maximum. Many species also have small dispersal ranges which increases their risk of extinction through small changes in habitat or environment.