Currently in Miami — July 26, 2023: Wind shift to subtract a couple of degrees

The weather, currently.

Not much rain is expected on Wednesday as high pressure starts to creep in from over the western Atlantic and the last remnants of dry Saharan dust linger over South Florida. The isolated to scattered showers that do form will be focused toward the interior as easterly winds keep them away from the east coast metro area. This shift in winds, which had been blowing from the southwest the last several days, will alleviate some of the dangerous heat along the east coast, bringing temperatures down into the low to mid 90s. However, that is still well hotter than normal and feels-like temperatures will remain between 105-110 degrees due to additional humidity, therefore the Heat Advisory will likely continue across all of South Florida on Wednesday.

El tiempo, actualmente.

Se espera poca lluvia el miércoles a medida que un área de alta presión se acerca desde el Atlántico occidental y los últimos restos de polvo seco del Sahara permanecen sobre el sur de Florida. Los aguaceros aislados a dispersos que se formen se enfocarán hacia el interior a medida que los vientos del este los mantengan alejados del área metropolitana de la costa este. Este cambio en los vientos, que habían estado soplando desde el suroeste en los últimos días, aliviará parte del calor a lo largo de la costa este, lo que hará que las temperaturas bajen a los rangos bajo a medio de los 90 grados. Sin embargo, esto sigue siendo más caliente que lo normal y la sensación térmica se mantendrá entre 105 y 110 grados debido a la humedad adicional, así que es probable que la Advertencia de Calor continúe en todo el sur de Florida el miércoles.

—John Morales

What you can do, currently.

The climate emergency doesn’t take the summer off. In fact — as we’ve been reporting — we’re heading into an El Niño that could challenge historical records and is already supercharging weather and climate impacts around the world.

When people understand the weather they are experiencing is caused by climate change it creates a more compelling call to action to do something about it.

If these emails mean something important to you — and more importantly, if the idea of being part of a community that’s building a weather service for the climate emergency means something important to you — please chip in just $5 a month to continue making this service possible.

Thank you!!

What you need to know, currently.

A new study, out Tuesday in the prestigious journal Nature Communications, has found that a key ocean current in the Atlantic is now expected to collapse by 2050, and as early as 2025.

The Atlantic Meridional Overturning Circulation (AMOC), the collapse of which was famously exaggerated in the movie The Day After Tomorrow, has collapsed many times in the past, most recently 12,000 years ago towards the end of the last ice age. Scientists think excessive meltwater coming from Greenland could be already pushing it toward another collapse, with the current now at its weakest in 1,600 years.

The most recent IPCC assessment concluded that a AMOC collapse is unlikely this century, and that global warming in excess of 8°C may be needed. A study published just seven years ago suggested just a 44% of a collapse by the year 2300, assuming Paris emissions reductions targets are met.

The new study uses a new method to estimate the effect of current and future emissions on the strength of the current and estimates a collapse by 2050, with a 95% confidence interval of 2025–2095. According to one of the researchers who helped collect some of the study’s data back in 2005, “it is mind boggling that almost 20 years later we are seriously looking at a collapse scenario in our lifetimes.”

German oceanographer Stefan Rahmstorf, whose past work has included study of the AMOC, has an extremely helpful 10 point overview of the study and how it has changed is view of what’s possible, including the possible likelihood of a near-term collapse.

The effects of a near-term collapse of the AMOC cannot be understated. The northward current provides warmth to the Gulf Stream that, if halted significantly, would sharply cool Northern Europe and worsen its shift towards drought while most of the rest of the world continues to warm. With the ocean no longer able to as effectively transfer heat between the Caribbean and Europe, Atlantic storms could greatly intensify in frequency and severity — according to research conducted by super scientist James Hansen.

Such consequences would be so dire that, according to the researchers, they should be “avoided at all costs”. In my person opinion — if there was ever a study that justifies world leaders declaring a climate emergency and winding down fossil fuels, it’s this one.

—Eric Holthaus