Delta variant triggers dangerous new phase in the pandemic
From New Delhi, the variant has quickly spread, and it now looks set to sweep the globe in what could be a devastating new wave. In the United Kingdom, Delta already makes up more than 90% of all infections; it has driven COVID-19 case numbers up again after a dramatic decline and led the government last week to postpone the final stage of its reopening plan.
The two effects—increased transmissibility and immune evasion—are hard to disentangle, but
https://www.sciencemag.org/news/2021/06/delta-variant-triggers-dangerous-new-phase-pandemic
How climate change 'loads the dice' for heat waves
This week's sizzling temperatures may herald a climate reality that scientists thought was still decades in the future.
The intensity of the heat, particularly in a region of the country known for its mild conditions, has been shocking, said Nicholas Bond, a research scientist at the University of Washington and Washington's state climatologist.
"The tropical cyclones tend to disrupt the jet stream all across the Pacific Ocean," O'Neill said, adding that they can affect both high- and low-pressure systems. "If we get a tropical cyclone, we're three times more likely to get a high-pressure ridge set up close to where we see this one."
Average temperatures in the Pacific Northwest have warmed by roughly 1.3 degrees since 1895, according to the University of Washington's Climate Impacts Group, and most cities in the region feel more than 2 degrees warmer in the summer than they did in 1970.
https://www.nbcnews.com/science/environment/heat-wave-west-coast-hints-climate-change-scientists-say-rcna1297
What causes an ice age and what would happen if the Earth endured another one?
The Earth has been alternating between long ice ages and shorter interglacial periods for around 2.6 million years.
For the last million years or so these have been happening roughly every 100,000 years - around 90,000 years of ice age followed by a roughly 10,000 year interglacial warm period.
The onset of an ice age is related to the Milankovitch cycles - where regular changes in the Earth's tilt and orbit combine to affect which areas on Earth get more or less solar radiation.
When all these factors align so the northern hemisphere gets less solar radiation in summer, an ice age can be started.
https://www.abc.net.au/news/science/2016-06-15/what-is-an-ice-age-explainer/7185002
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