The effect of climate change extends beyond ruining Earth's environment and our physical safety. A report published this week suggests that climate change has a negative effect on our mental health, too.

The study, published in the journal Proceedings of the National Academy of Sciences of the United States(PNAS), links an increase in monthly temperatures to a rise in mental health issues. The experimental evidence stems from meteorological(气象的) data paired with information collected from nearly 2 million randomly sampled residents in the United States. The data was collected over the span(跨度) of a decade.

"We find that experiences with hotter temperatures and added rainfall each worsen mental health, that long-lasting warming associates with an increased popularity of mental health issues, and that exposure to tropical cyclones(热带气旋), likely to increase in frequency in the future, is linked to worsened mental health," authors of the study stated. "These results provide added large-scale evidence to the growing link between climate change and mental health. "

The report specifically focused on mental health outcomes due to the effects of environmental stress - such as temperature, rainfall, and tropical cyclones - but other climate change-related issues are likely to affect mental health as well - specifically, the stress and anxiety of knowing natural disasters could be more frequent as temperatures rise.

A study conducted by Cornell University examined how the use of AI in conversations impacts the way people express themselves and view each other.

The researchers have found people have more efficient conversations, use more positive language and perceive each other more positively when using an Al-enabled chat tool.

However, the group also found that when participants think their partner is using more AI-suggested responses, they consider that partner as less cooperative.

"I was surprised to find people tend to evaluate you more negatively simply because they suspect you're using AI to help compose text, regardless of whether you actually are," said Jess Hohenstein, the lead researcher. "This illustrates the continuous overall doubt that people seem to have around AI."

For their first experiment, participants were asked to talk about a policy issue and assigned to one of three conditions: both participants can use smart replies; only one participant can use smart replies; or neither participant can use smart replies. Researchers found that using smart replies increased communication efficiency, positive emotional language and positive evaluations by communication partners. On average, smart replies accounted for 14.3% of sent messages.

But participants who their partners suspected of responding with smart replies were evaluated more negatively than those who were thought to have typed their own responses, consistent with common assumptions about the negative implications of AI.

"While Al might be able to help you write," Hohenstein said, "it's altering your language in ways you might not expect, especially by making you sound more positive. This suggests that by using text-generating Al, you're giving up some of your own personal voice."

Malte Jung, an associate professor, said, "What we observe in this study is the impact that Al has on social dynamics and some of the unintended consequences that could result from integrating AI in social contexts. This suggests that whoever controls the algorithm(算法) may have influence on people's interactions, language and insights into each other."

Hikes in grocery prices often arise from factors outside of governments' control, whether it's bird flu driving up egg costs or heavy rain in California drowning crops. But farmers can gain more control over the availability of certain foods by using satellite data, finds a new study led by researchers from University of Maryland. 

Remote sensing has long been used to track and make predictions about crop harvests. But governments have been hesitant to heavily invest in the technology for crop monitoring and planting because they lacked evidence of the ability to produce quantifiable economic benefits-until now. 

"The models we created show that remote sensing forecasting can reduce food prices in import-dependent countries by 1.1%~12.5%," said Laixiang Sun, a professor in the Department of Geographical Sciences. "By using remote sensing to predict a poor harvest in the Northern Hemisphere(半球), the Southern Hemisphere can plant more to avoid a shortage. If the Northern Hemisphere has a good harvest, the Southern Hemisphere can plant less to avoid an oversupply. This will keep prices stable."

The researchers first created models to predict how much warning farmers in the opposite hemisphere could have of potential shortages or surpluses. To do so, the researchers used remote-sensing data before a 2008 poor wheat harvest in, Russia, a 2012 good wheat harvest in Ukraine, and 2012's poor soybean harvest in Brazil. The wheat-forecasting models accurately predicted production in 2008 and 2012 two months before the harvests.

The researchers also developed economic models to show how predictions of upcoming shortages and surpluses could prevent food price changes. With data from 2007 and 2011, the years immediately before the wheat and soybean harvests, the models showed that consumers in import-dependent countries could save some money if farmers could see and respond to the predicted harvests in the opposite hemisphere. 

Sun said the findings justify continued monitoring of crop growth from space—and not a moment too soon, either. "This is important, as global food security is increasingly threatened by regional human conflicts and extreme weather events from climate change," he said.