Question

how does climate influence weather? climate only determines short term atmospheric conditions, climate has no influence on weather, climate shapes long term weather patterns

Answer 1

Short answer: climate does influence weather — but not deterministically. Weather is the atmosphere’s short‑term state (hours to weeks); climate is the long‑term statistics (averages, variability, and extremes) of weather over decades. Climate sets the background conditions and probabilities that shape how weather will behave.

Comments on the three statements you listed
- "climate only determines short term atmospheric conditions" — incorrect. Short‑term conditions are weather; climate does not "only determine" them, it provides the statistical context from which short‑term weather arises.
- "climate has no influence on weather" — incorrect. Climate influences the frequency, intensity, timing and regional distribution of weather events.
- "climate shapes long term weather patterns" — correct. Climate describes long‑term patterns and trends that affect weather statistics.

How the influence works (key mechanisms)
- Statistical framing: climate is the probability distribution (mean, variance, extremes) from which individual weather events are sampled. Think: weather = one dice roll, climate = how the dice are weighted.
- Temperature shifts: a warmer climate raises average temperatures and shifts the distribution so heatwaves become more frequent and cold snaps less frequent.
- Moisture and precipitation: warmer air holds more water vapor (~7% more per °C via Clausius–Clapeyron), increasing the potential for heavier rainfall and more intense storms.
- Ocean–atmosphere interactions: warmer sea surface temperatures change storm development and hurricane intensity and can modify storm tracks.
- Circulation changes: long‑term changes (e.g., Hadley cell expansion, jet‑stream shifts, Arctic amplification) alter where storms and precipitation tend to occur, and can make some patterns more persistent (blocking).
- Changing extremes: climate change alters the odds — more extreme heat, heavier precipitation in many regions, different drought patterns — even though individual storms remain weather events.
- Natural variability and chaos: internal variability (El Niño/La Niña, PDO, Arctic Oscillation) and the chaotic nature of the atmosphere mean weather remains unpredictable beyond certain time horizons; climate changes the baseline and probabilities but not the exact day‑to‑day outcome.

Examples
- El Niño is a climate pattern (ocean–atmosphere mode) that changes seasonal probabilities of rain, wind, and temperature across large areas.
- Global warming has increased the frequency and intensity of heatwaves and heavy precipitation events in many regions.
- Loss of Arctic sea ice can influence midlatitude weather patterns (e.g., jet‑stream waviness), potentially affecting the persistence of cold snaps or storms.

Takeaway
Climate doesn’t single out particular weather events, but it shifts the baseline and the odds: it shapes long‑term patterns and changes how often, how intense, and where different kinds of weather occur.