natural variability

A forest does not live in a static world. Between winter and summer, day and night, conditions shift, and each fluctuation is like a rhythm that all its inhabitants must keep pace with. Yet until now, ecologists have mostly studied how communities of living beings persist in an unchanging environment, like testing a bridge's strength only in calm weather.

Rare species in a large community are like thin branches on a tree: a random gust can easily snap them. Even if conditions are stable, a small population simply lacks enough individuals to survive a bad season. In a new study, scientists added this factor to an ecosystem model and watched the community clean itself out.

A superfluid gas is like a crowd of people marching in step: each atom knows where to go and doesn't fall out of the common rhythm. But this crowd has three 'valleys'—three different directions it can take. In a new experiment, physicists made one valley slightly more 'favorable' than the others and watched how the crowd darted between them.

A protein chain folds into a working tool in a fraction of a second, and almost never makes a mistake. For a long time, it was thought that evolution specifically polishes amino acid sequences so that a protein not only works but also easily finds its unique shape. New work turns this idea on its head.

When two black holes merge, ripples spread across the fabric of spacetime — gravitational waves. But what if one of them isn't a run-of-the-mill black hole but something else — an exotic compact object?

At the dawn of time, the universe experienced a brief moment of frantic expansion — inflation. Tiny quantum jitters of spacetime stretched to cosmic scales. These jitters, primordial fluctuations, became the seeds from which galaxies and stars later grew.

A translator in a conference hall tries to convey the speaker's words, but the hall is noisy: someone coughs, chairs creak, and the street outside is loud. If the speaker lowers their voice, the translator still keeps translating, but their voice drowns in the noise.

A student who has spent years solving problems from other people's textbooks suddenly receives three notebooks with real ocean observations. There are few problems, but they have already seen hundreds of similar ones, and now a couple of examples suffice to catch the new teacher's style.

Two pendulums suspended from a single invisible spring swing in a shared air current. One always lags the other by exactly half a period: when the first swings left, the second is already returning from the right. By watching the first, you can tell where the second will be half a period later.

Every winter, the tropical Pacific Ocean seems to replay the same script: sea surface temperatures off the coast of Peru rise, trade winds weaken, and a wave of droughts and floods spreads across the planet. This is El Niño, and its peak almost always falls in December. Why winter in particular?

A tuning fork produces a pure tone, but if you strike it too hard, it starts to rattle, and a musician might mistake that rattle for complexity in the sound.

Drylands are like skin cracking from dehydration. When rainfall decreases, plants don't vanish overnight: they rearrange, leaving bare patches of soil between them. These patterns are visible even from space. Scientists compared satellite images of eight arid regions, from the Sahel in Africa to Australian deserts.

For 800,000 years, ice ages have occurred every 100,000 years. The rhythm matches the elongation of Earth's orbit. But the orbit changes the flow of solar heat so subtly — as if the conductor barely moved the baton, yet the orchestra thundered. It remained a mystery how this weak signal controls the ice sheets.

The ocean does not shout about its intentions. It whispers: a warm patch off the coast of Peru, a cold tongue near Hudson Bay, a barely perceptible shift in a current. The atmosphere does not respond immediately, and by winter Europe may get either mild slush or Siberian frosts.

Two pendulums hang on the same wall, swinging out of sync, but suddenly they move as one, only with an 18-month delay. One pendulum is the Indian monsoon, the seasonal wind that brings rain to South Asian farmland. The other is the deep water of the tropical oceans, which slowly accumulates heat and remembers it for years.

Imagine a radiator in a room: it heats up, but if its surface is clogged with dust, heat escapes less efficiently. Something similar is happening to our planet. Earth receives energy from the Sun and must radiate the excess back into space, otherwise temperatures rise. Scientists call this ability to shed excess heat radiative feedback.

Every few years, the Pacific Ocean off Peru warms so abruptly that fish disappear and rains flood the desert. This phenomenon is called El Niño, and it acts like a pendulum that swings the planet's climate. But when the planet itself warms, the pendulum behaves strangely: first its swing widens, then it suddenly fades.

An ecosystem is like a swing that someone is subtly pushing. Previously, it was thought that the main concern was that the swing wouldn't swing too wildly. But the authors of this work showed that the greater danger is when the equilibrium point itself slides toward a place where the swing can no longer return.

Eclipses in binary stars are like clockwork: a white dwarf (the dense remnant of a star) regularly passes in front of its companion, and the light briefly dims. But for most such pairs, the clock runs fast or slow by seconds over years. Astronomers measured these glitches in 43 systems and found a pattern.

The bronze plates of a gamelan do not sound according to a single tuning standard: each orchestra on Java keeps its own tuning, and two neighboring ensembles may play the same melody in slightly different intervals.

Two barometers hang on the wall. One reads clear, the other says partly cloudy. Which weather do you trust? That is roughly the question facing a group of climate scientists when two independent methods predicted different futures for the Pacific Ocean in 2026.

Every few years, the warm current off the coast of Peru shifts, and fishermen come home empty-handed. This is El Niño, the breath of the tropical Pacific, which affects weather from Indonesia to California. Predicting its arrival is as hard as predicting where a stone thrown into a raging river will roll.

The Parker Solar Probe and Solar Orbiter spacecraft fly close to the Sun and measure the solar wind — the stream of charged particles that constantly blows from our star.

Glaciers don't just darken from soot. Their surfaces host tiny algae that, as temperatures rise, bloom and turn the ice dark. Dark ice absorbs more sunlight, melts faster, and further warms the planet. It's like how a black t-shirt in the sun gets hotter than a white one. The second player in overheating is forests.

The Pacific Ocean breathes slowly and deeply. Every few years, its warm surface waters shift eastward toward the coast of South America, and then Peru gets drenched while Australia goes up in flames. A year or two later, the water retreats, and the picture flips. This breathing is called El Niño, and until now its rhythm could only be guessed a couple of steps ahead.

The tropical Pacific Ocean heats and cools like a giant battery, and its rhythm affects weather from India to Canada. This rhythm is called El Niño–Southern Oscillation, or ENSO for short. Forecasting it months ahead is like predicting when a pot will boil without knowing the strength of the flame.

A warm ocean off the coast of Peru can make winter in Moscow unusually mild. Climate scientists call these invisible threads that link weather in distant corners of the planet teleconnections. For a long time, they were thought of as something like permanent wiring: the signal sources may pulse, but the wires themselves lie still.

The Pacific Ocean is like a giant swing: warm water piles up in the west, then slides toward the east, and the temperature off the coast of South America jumps. Such warm years are called El Niño, and cold ones La Niña. But the swing doesn't move on its own: it's pushed by the wind.

Every day, about 40,000 thunderstorms flash across the planet. In that moment, the atmosphere resembles an orchestra without sheet music: warm air rises like a bow stroke, winds aloft carry the melody, and lightning punctuates the finale. But who conducts this orchestra?

An orchestra of a thousand musicians plays in harmony as long as the conductor keeps the tempo. But the moment he changes the score, the violins in one corner start playing louder, while the brass in another come in late.

Two conductors stand before one orchestra. One waves the baton quickly, setting the tempo every few bars. The second is almost motionless, but his slow breathing changes the overall sound throughout the symphony. So it is in the tropical Pacific: one part of the wind governs the fast oscillations of El Niño, the other governs decadal climate shifts.

The climate of the United States is not a straight line creeping upward. It is an orchestra without a conductor, where every violin and every drum plays its own part, and together they create an intricate pattern of warm and cold, wet and dry years.

A camera on a tripod shoots the same landscape for decades. If you don't touch the lens, the images get hazy: the landscape changes, but the focus stays put. That's roughly how climate norms work. According to World Meteorological Organization rules, they are calculated as the average over the last 30 years.

Imagine a pendulum that is pushed in time with the seasons: harder in winter, softer in summer. But this pendulum has a quirk: a switch that operates with a delay. When the pendulum passes through zero, the switch clicks and changes the direction of the push. That is exactly how the simplified El Niño model built by mathematicians works.

The ocean hums like a crowded hall: in one corner, voices argue about decades; in another, about years; in a third, about the changing seasons. To pick apart these voices, climatologists used to rely on filters they tuned themselves, letting through only slow waves or only fast ones. But the Pacific plays by its own rules: a warm patch off the coast of Peru can be a brief spike or part of a long-term rearrangement.

The tropical Pacific Ocean lives in two rhythms. The first is fast: a wave of thunderstorms born over the Indian Ocean races eastward and dies out off the coast of the Americas within a month or two. The second is slow: every few years, the ocean surface warms enough to alter weather across the entire planet. That is El Niño. Between these rhythms lies a bridge, and building it took climatologists decades.

You can sit on a seesaw and pump your legs, or you can just tip from one side to the other. The Pacific Ocean does both. Every few years, warm water off the coast of Peru gives way to cooler water, and rainfall patterns, winds, and entire ecosystems across half the planet reshuffle. These shifts are called El Niño and La Niña, together known as ENSO: Earth's climate seesaw.

Picture a pendulum hanging in a room with drafts. Sometimes a gust pushes it harder, sometimes softer. If the pendulum barely loses energy, it will swing long and steady. But if friction is strong, each push quickly fades, and the motion becomes jerky: a sharp swing, then a long sway. That's exactly how the tropical Pacific behaves when the heat of El Niño gives way to the cold of La Niña.

The Pacific Ocean breathes. Every few years, its warm western "lung" exhales eastward, and from Peru to Indonesia, rains, droughts, and hurricanes shift. This breath is called El Niño–Southern Oscillation, or ENSO.

The Pacific Ocean is a giant network of nerve endings that warns of an impending attack a year in advance. In 2023–2024, El Niño, the warm phase of the Pacific climate oscillation, pushed global temperatures to record highs. Now, two independent methods, like two doctors examining the same symptoms, agree: no new attack in 2025.