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Suppression of dipolar oscillation modes by strong magnetic fields in the cores of intermediate-mass red giant stars reveals that powerful magnetic dynamos were very common in the previously convective cores of these stars.
The age of a young to middle-aged star can be determined from how quickly or slowly it rotates, but the relationship breaks down for old stars; models now show that old stars are rotating much more quickly than expected, perhaps because magnetic winds are weaker and therefore brake the rotation less effectively.
If the 2-degree warming threshold of the Paris agreement is exceeded, Mediterranean ecosystems will change beyond anything seen over the past 10,000 years.