Earth's atmosphere is a complicated dance of molecules involving the output of plants, animals and human industry in sequences of chemical reactions.

Such processes help maintain the atmosphere's chemical balance; most topically during protest week in New York City, they break down pollutants emitted from the burning of fossil fuels.

Understanding exactly how these reactions proceed is critical for predicting how the atmosphere will respond to environmental changes, but some of the steps of this dance are so quick that all of the molecules involved haven't been measured in the wild.

Ryan Rykaczewski, an oceanographer and assistant professor at the University of South Carolina, is part of a team that are looking deep into the ocean's past, and they have shown that natural processes can cause dramatic year-to-year drops in fish populations and growth rates.

They also raise questions about whether human activities might be making those declines more frequent.

Upwelling means phytoplankton, the perfect 'sea food'

The focus of the research is the California current, which stretches from Washington state to the Baja peninsula and is one of a handful of coastal waters on Earth from which an inordinately large portion of the world's fish harvest originates.

Outside the developed world, global population continues to rise but all of the best agricultural locations are in use. If we want people to be self-sufficient (and we do) science is going to need to be able to help the developing world with innovative and sustainable solutions.

Modern agriculture has not reached any kind of limit, we can easily boost food production by as much as 70-100% in the next few decades. To grow in more difficult areas, and to be resistant to swings in weather, more drought-tolerant food crops are essential.  

By Robin Wylie, University College London

The very small is very weird; I explained that the last time in Small Is Ugly 1 already with help of the example of water being in the driest of places (Vastness and Fastness of the Small helps Evolution is of course somewhat related). And today, I still do not mean supposed "quantum weirdness", which is not about small stuff.

Antidepressants are the most commonly used treatment for social anxiety disorder but we know they don't work for many people and their efficacy goes down over time.

New research finds they are not even needed in many instances. 

Social anxiety disorder is a condition characterized by fear and avoidance of social situations. It affects as many as 13 percent of the Western world. For most people, it is not severe, and they never receive treatment for the disorder but those who do get treatment are usually assigned medication.

The appeal of artificial photosynthesis, in which the electrochemical reduction of carbon dioxide is used to produce clean, green and sustainable fuels, is that we can turn an atmospheric byproduct into a renewable energy technology.

However, finding a catalyst for reducing carbon dioxide that is highly selective and efficient has proven to be a huge scientific challenge.

Peidong Yang, a chemist with Berkeley Lab's Materials Sciences Division, led a study in which bimetallic nanoparticles of gold and copper were used as the catalyst for the carbon dioxide reduction. The results experimentally revealed for the first time the critical influence of the electronic and geometric effects in the reduction reaction.

By Nick Bostrom, University of Oxford