The researchers believe the phenomenon is being driven primarily by cloud cover.
Climate change is causing nights to be “disproportionately” warmer than days in many parts of the world, according to scientists.
Researchers found warming at night-time is more common than during the day in over half of the land surfaces across the planet.
It could have a “potentially significant” impact for nocturnal animals, according to a study published in the journal Global Change Biology.
The team from the University of Exeter looked at climate change records from 1983 to 2017.
They found that night-time temperatures were, on average, more than 0.25C warmer when compared to daytime temperatures.
The researchers believe the phenomenon, known as “warming asymmetry” is being driven primarily by clouds.
Clouds cool the planet’s surface during the day but retain warmth overnight.
Lead author Dr Daniel Cox, of the Environment and Sustainability Institute on Exeter’s Penryn Campus in Cornwall, said: “We demonstrate that greater night-time warming is associated with the climate becoming wetter, and this has been shown to have important consequences for plant growth and how species, such as insects and mammals interact.
“Conversely, we also show that greater daytime warming is associated with drier conditions, combined with greater levels of overall warming, which increases species vulnerability to heat stress and dehydration.
“Species that are only active at night or during the day will be particularly affected.”
He added: “Warming asymmetry has potentially significant implications for the natural world.”