Announced earlier today, Carbon dioxide levels measured at NOAA’s Mauna Loa Atmospheric Baseline Observatory peaked at 423 parts per million in May, continuing a steady climb further into territory not seen for millions of years. NOAA
Meteorologists have been left stunned by a record heat index for the Northern tier of Puerto Rico and the British Virgin Islands as a rare heat dome settles over parts of the Caribbean region. Heat-index temperatures could reach up to 127 degrees Fahrenheit today.
The National Weather Service has issued a watch for life-threatening heat for island residents. Night-time temperatures are hot, and power outages have been reported. There is scarce information on the heat wave in any capacity other than Jeff Berardelli.
Life-threatening heat today in Puerto Rico so hot that some meteorologists are astonished. And more of the same to come this week. Heat index numbers as high as 115-125 today!! So what is going on? There are many factors, so let's dig in... thread 1/
A pocket of Saharan dust is right over the island, leading to clear weather, helping boost temperatures. But there's a lot more....
Zoom out and we see a culprit. A large/ intense high (heat dome) forming just east of Puerto Rico, unusually far south, leading to a SE flow and drawing up high humidity. But also record warm Tropical Atlantic water temperatures helping boost dewpoints...
Yes the warm water is partially due to climate change, so it is a factor. Tropical ocean temps have warmed by ~2F. Also the natural distribution of "anomalously" warm water this year favors the tropics. Last summer it favored the North Atlantic... but there's more...
Now we arrive at the Wavy jet stream. The pattern right now is ludicrous in/ around North America. Blocky is an understatement. Some may be due to Typhoon Mawar's added wave breaking energy. But we are seeing these blocks more often especially during spring/ summer...
There's a lot of work being done to figure out the link between climate change, blocks and the wavy jet. The loss of sea ice and uneven heating at the poles is likely a factor in high latitude blocks. This leads to a very amplified pattern, big blocky lows and heat domes...
Next, we have a developing El Nino adding tons of energy to the mix. The subtropical jet is screaming, but that is more of a winter time phenomena than summertime for El Nino. With that said, when you overlay that on the prevailing pattern I can only surmise it amplifies...
The bottom line: As we go deeper into 2023 and El Nino intensifies, we should expect a stunning year of global extremes which boggle the meteorological mind. The base climate has heated due to greenhouse warming and a strong El Nino will push us to limits we have yet to observe.
The National Weather Service defines a heat dome as:
The heat index, also known as the apparent temperature, is what the temperature feels like to the human body when relative humidity is combined with the air temperature. This has important considerations for the human body’s comfort. When the body gets too hot, it begins to perspire or sweat to cool itself off. If the perspiration is not able to evaporate, the body cannot regulate its temperature
What happens in the Arctic does not stay in the Arctic.
The Revolution Will Not Be Air-conditioned: For every unit of heat removed by air-conditioning from an interior space, roughly 1.1 units of heat are added to the exterior atmosphere*, 0.1 of which must be supported by the electrical grid. Electrical grid overloads and failures will become common, and may even become permanent over many weeks at a time (cf. Texas, winter 2021).
*cf. The Second Law of Thermodynamics.
This diagram (augmented for relevance) shows various physical relationships between air and the amount of moisture it holds under various temperature conditions.
1. The vertical lines are lines of constant ambient air temperature; for example everywhere equal to 80F on the vertical 80F line.
2. The horizontal lines are lines of equal moisture content; for example everywhere equal to 0.016 pounds of water vapor per pound of dry air on the horizontal 0.016 line.
3. The sweeping curves are the loci of equal per-cent relative humidity, i.e., the ratio of the vapor in the air at a point to the most vapor it could possibly hold at 100% relative humidity. At 100% RH we call the air saturated with moisture—it cannot take on any more. Evaporative cooling ceases.
4. The straight sloping lines are more mysterious; they represent the temperature a wet rag would cool down to if held up in the ambient wind as it dried—your wet swim suit in a gale. The interesting—and crucial—thing about this is that from any air temperature starting point on a sloping line—say 80F/60%RH—the evaporative cool-down end-point is always the same, 70F! Check out: 100F/20%RH. This end point is called the wet-bulb temperature because it is measured with a thermometer whose bulb, cooled in the wind, is covered with a wet sock.
Most media do not report this phenomenon any more than they do on any other climate crisis issue.
