Climate frequently asked questions

Greenhouse gases are atmospheric gases that intercept long-wave (mainly infrared) radiation emitted from the Earth's surface.
Carbon is a very common element, present in plants, animals, the atmosphere, ocean, and rocks. It naturally moves between these forms by many processes, learn about some here.
The greenhouse effect is a warming of the earth's surface and lower atmosphere caused by substances which let the sun's energy through to the ground but impede the passage of energy from the earth back into space.
El Niño and La Niña refer to opposite extremes of the ENSO cycle, when major changes in the Pacific atmospheric and oceanic circulation occur.
It was the atmospheric part of ENSO - (called the "Southern Oscillation" or "SO"), that first attracted the attention of scientists. It is one of several persistent patterns of high and low pressures around the globe.
Although ENSO events have an important influence on New Zealand's climate, it accounts for less than 25% of the year to year variance in seasonal rainfall and temperature at most New Zealand measurement sites.
The Intergovernmental Panel on Climate Change (IPCC) is charged with assessing the most up to date scientific, technical and socio-economic research in climate change.
Future climate changes will be affected, amongst other things, by how much extra greenhouse gas goes into the atmosphere.
Greenhouse gases have continued to increase in the atmosphere. This is due largely to human activities, mostly fossil fuel use, land-use change, and agriculture.
Information about past climate is obtained from piecing evidence together from various sources.
The Earth's climate has exhibited marked "natural" climate changes, with time scales varying from many millions of years down to a few years.
NIWA identified in August 1998 that a significant shift in the New Zealand climate has occurred during the past 20 years.
In the absence of rain, most of the flow in a river is water that drains slowly from the ground.