Southern Hemisphere

"And with a climate mode such as SAM stuck in its positive, fire-prone phase that seems to amplify climate change, it doesn Multi-function nozzles factory look good.The Indian Ocean Dipole, or IOD, is a similar ocean-atmospheric phenomenon characterized by changes in sea-surface temperatures between the eastern and western part of the Indian Ocean, while the Southern Annular Mode or SAM, describes the north-south movement of the westerly wind belt that circles Antarctica and carries moisture to the southwest corners of all the Southern Hemisphere continents. The recent positive trends in SAM are attributed to increasing greenhouse gas levels and the hole in the ozone layer.

The study found that of the three climate drivers, the SAM had the strongest impact on fire activity - both lightning- and human-caused wildfires - due to a combination of lower precipitation and higher temperatures, said Holz..The study appears in the journal Geophysical Research Letters."But Holz cautioned that it does not mean that there will be an increasing number of fires everywhere.On the flip side, areas that are dry year-round will likely see a decline in fire activity with global warming unless there's a strong increase in rainfall.Washington: Climate change is responsible for many disasters across the world. That trend is expected to continue. A new catastrophe can now be added to the list. Under warmer conditions, if precipitation stays constant, there will be increased fire activity in areas that already have plenty of fuel to burn but have historically been too humid or wet to burn.

Heat, oxygen, fuel and an ignition source combine to start wildfires, but where and how quickly a fire moves depends on the terrain, the types, and condition of vegetation present and the weather, said Andres Holz, the study's co-lead author.Climate change is amplifying climate-fire teleconnections, or the strength of long-distance relationships between weather patterns and fire During the onset of the 21st century, lightning-ignited fires were tightly coupled with upward trends in the SAM and rising temperatures across the Southern Hemisphere"We think that by having warmer oceans and warmer temperatures in general, we're going to see higher evaporation and heat transfer, and thus higher frequency of convective storms that in turn results in more lightning-ignited fires," Holz said.The study examined the observed and forecasted relationship between lightning-ignited fires, rising temperatures across the Southern Hemisphere and natural climate variability in three leading climate drivers that affect weather worldwide: El Niño-La Niña, the Indian Ocean Dipole, and the Southern Annular Mode.El Niño-La Niña, known as ENSO, is the periodic warming and cooling periods of the equatorial eastern and central Pacific Ocean that affects the world's climate the most. "Now the winter is not as rainy and the summer is longer, drier and warmer," Holz said.

During the positive phase of SAM, the westerly winds contract toward Antarctica, leaving large areas in southern South America, South Africa, and Australia rain-free.The study found that the natural influence of the three climate modes on fire activity was stronger during the 21st century than during the last couple of decades of the 20th century as a result of anthropogenic warming. "These trends are expected worldwide, not just in the Southern Hemisphere," Holz said.Drier winters mean less moisture on the land, and warmer springs and summers are pulling the soil moisture into the air more quickly, allowing the soil and vegetation to dry out and ignite more readily, he said.