Tuesday, August 18, 2026

Water_Temps

 Sometimes, in the evening after working on a blog, I just chat with Copilot about

odds and ends that I feel might make things clearer. Grab a pack of cookies, and lets have

a run...

Copilot:

Does anything analogous to ENSO occur in the Atlantic?

Yes — the Atlantic does have an ENSO‑like phenomenon, but it is smaller, weaker, shorter, and behaves a bit differently.

The scientific name is the Atlantic Niño (also called the Atlantic Equatorial Mode), and it is widely described as El Niño’s “little brother.” 

Below is the clearest, structured explanation of how it compares to ENSO.

🌊 Concise takeaway

The Atlantic has its own ENSO‑like warm/cool cycle called the Atlantic Niño, driven by weakened or strengthened trade winds and changes in the thermocline — the same physics as ENSO, but on a smaller scale.

It peaks in Northern Hemisphere summer, is shorter, and has more local impacts, especially on West African rainfall. 

🌍 What the Atlantic Niño is

A quasi‑periodic warm/cool cycle of sea‑surface temperatures in the equatorial Atlantic.

Dominant mode of year‑to‑year variability in that basin.

Often called the Atlantic Equatorial Mode.

Centered between 0° and 30°W longitude. 

It is analogous to ENSO because:

Warm events occur when trade winds weaken.

Cool events occur when trade winds strengthen.

The mechanism involves Bjerknes feedback, Kelvin waves, and thermocline depth changes — just like ENSO. 


🔁 How it differs from ENSO

1. Smaller amplitude

Atlantic Niño SST anomalies are about half the strength of Pacific El Niño events.


2. Shorter duration

Atlantic Niño peaks in June–August, whereas ENSO peaks in December–February.


3. More localized impacts

ENSO affects global climate.

Atlantic Niño mainly affects:

West African monsoon rainfall

Sahel drought/flood patterns

Northeastern South America rainfall  


4. Different basin geometry

The Atlantic is narrower, so:

SST anomalies are strictly equatorial

There is no east–west sign reversal like in ENSO


🧠 Key physical mechanism (same as ENSO)

Atlantic Niño is driven by:

Weakened trade winds → warm water moves east → thermocline deepens → warm SSTs

Strengthened trade winds → cold upwelling intensifies → thermocline shoals → cool SSTs

This is the same Bjerknes feedback that powers ENSO.


🌡️ Two types of Atlantic Niño

Recent research shows two distinct variants:

Central Atlantic Niño — warming centered in the central basin

Eastern Atlantic Niño — warming near West Africa, triggered by Kelvin waves  


🔗 Does ENSO influence the Atlantic Niño?

There may be a weak, occasional connection, but it is not consistent.

Some studies show ENSO can help trigger Atlantic Niño under certain conditions, but the relationship is tenuous.

🎯 Bottom line

Yes — the Atlantic has an ENSO‑like oscillation, but it is:

Smaller

Shorter

More localized

Less predictable

Less globally influential

Still, it is extremely important for West African climate, Atlantic hurricane behavior, and regional rainfall variability.

If you want, I can compare Pacific ENSO vs Atlantic Niño in a side‑by‑side table, or explain why the Atlantic version is weaker (hint: basin geometry + thermocline structure).


It looks like this might be a year with NO hurricanes in the Atlantic.

Louise, I get why it feels like this might be a hurricane‑free year — the Atlantic has been strangely quiet so far. But the science says something very different: a quiet early season does not mean a quiet full season, and 2026 is not shaping up to be a no‑hurricane year.

Let me give you the clearest breakdown of what’s actually happening.


🌡️ 1. The Atlantic can be dead quiet… until suddenly it isn’t

Historically, many hyperactive seasons began with no named storms through July.

Examples:

2004 (Charley, Ivan) — no storms until July 31

2017 (Harvey, Irma, Maria) — extremely quiet early, then exploded

2020 (record-breaking 30 storms) — slow start, then nonstop activity


The Atlantic often “wakes up” in late August and September, when:

African easterly waves strengthen

Shear drops

Ocean heat peaks

So a quiet early season is not unusual.


🌊 2. The Atlantic in 2026 is extremely warm

Sea‑surface temperatures (SSTs) in the Main Development Region (MDR) are well above average — the fuel hurricanes need.

Warm SSTs mean:

More moisture

More instability

More potential energy

A basin this warm almost never produces a “no‑hurricane” season.


🌬️ 3. ENSO conditions matter — and 2026 is transitioning

You’ve been studying ENSO, so here’s the key link:

El Niño suppresses Atlantic hurricanes (strong wind shear)

La Niña enhances them (low shear, rising motion)

2026 is showing signs of weakening El Niño / possible transition toward neutral, which typically opens the door for storms later in the season.

Even a neutral ENSO allows normal or above‑normal hurricane activity.


🌀 4. Zero hurricanes is essentially impossible

Since reliable records began (1851), the Atlantic has never had a season with:

Zero hurricanes

Zero named storms

Even the quietest seasons (1914, 1983) still had at least one hurricane.

The physics of the basin simply don’t allow a hurricane‑free year.


🧠 Why it feels quiet right now

Because:

Early-season storms depend heavily on local conditions

Shear has been high

Saharan dust outbreaks have been strong

The ITCZ has been slightly suppressed

But these are temporary.

Once the MDR moistens and shear drops, activity can ramp up very quickly.


🎯 Bottom line

No — 2026 is not on track to be a hurricane‑free year.

The quiet start is misleading.

The basin is warm, ENSO is shifting, and the peak season (Aug–Oct) hasn’t arrived.


If you want, I can:

Explain how ENSO affects hurricane formation

Show how SST anomalies predict storm intensity

Compare 2026 to past quiet‑start seasons

Walk through the physics of why hurricanes cluster in September

Just tell me what direction you want to explore.


ITCZ...

The ITCZ (Intertropical Convergence Zone) is absolutely central to how the tropics work — but it does not behave the way people intuitively expect. Let me give you the clearest, structured explanation of what it is, why it exists, and how it ties into ENSO and hurricanes.

🌍 What the ITCZ Actually Is

The Intertropical Convergence Zone is a band of rising air, thunderstorms, and heavy rainfall that circles the Earth near the equator.

It forms where the northeast trade winds (from the Northern Hemisphere) and the southeast trade winds (from the Southern Hemisphere) converge.

This convergence forces air upward, creating:

towering cumulonimbus clouds

intense rainfall

persistent convection

It is the single most important feature of tropical weather.


🌡️ Why the ITCZ Exists

Three physical reasons:


1. Maximum solar heating

The equator receives the most direct sunlight → warm surface → warm air → rising motion.


2. Converging trade winds

Air flows from subtropical high pressure belts toward the equatorial low pressure zone.


3. Coriolis effect is near zero

At the equator, winds blow straight, so convergence is strong and focused.


🧭 The ITCZ is NOT fixed — it migrates

This is the part most people miss.

The ITCZ moves north and south with the seasons:

Northward in Northern Hemisphere summer

Southward in Southern Hemisphere summer

Its movement follows the solar declination, not the geographic equator.


This migration is why:

West Africa has a monsoon

India has a monsoon

The Amazon has wet/dry seasons

Hurricanes form in certain months


🌊 ITCZ and ENSO

ENSO strongly affects the ITCZ:

During El Niño

The eastern Pacific warms

Convection shifts east

The ITCZ becomes more zonal (east–west)

Rainfall increases in the central/eastern Pacific

Atlantic ITCZ often weakens → fewer hurricanes


During La Niña

The western Pacific warm pool strengthens

Convection shifts west

The Atlantic ITCZ becomes stronger

More rising motion → more hurricanes

So the ITCZ is one of the main pathways through which ENSO affects global weather.


🌀 ITCZ and Atlantic Hurricanes

This is directly relevant to your earlier observation about a quiet Atlantic.

Hurricanes need:

warm SSTs

low wind shear

a strong ITCZ to generate tropical waves


If the ITCZ is:

weak, suppressed, or shifted south, early-season hurricane activity drops

strong, northward, or vigorous, hurricane activity increases

A quiet ITCZ in June–July is normal — it usually strengthens dramatically in August.

This is why the Atlantic can look dead until suddenly it isn’t.


🧠 A non‑obvious insight

The ITCZ is not a line — it is a heat engine.

It is the rising branch of the Hadley cell, the largest atmospheric circulation system on Earth.

Everything from ENSO to monsoons to hurricanes is tied to how this engine behaves.


🎯 If you want, I can go deeper into:

Why the ITCZ splits into two bands in the Pacific

How the ITCZ interacts with the Saharan Air Layer

Why the Atlantic ITCZ is the birthplace of most hurricanes

How ENSO shifts the ITCZ and changes global rainfall patterns

Just tell me which direction you want to explore next.


Why is Darwin considered in a hot zone...

Darwin is considered part of the “hot zone” of the Pacific for a very specific physical reason — and it has nothing to do with latitude alone. It’s because Darwin sits on the edge of the Western Pacific Warm Pool, one of the most important features in tropical climate dynamics.

Let me break it down clearly and intuitively.


🌊 Why Darwin is in the “hot zone”

⭐ 1. Darwin sits beside the Western Pacific Warm Pool

The warmest ocean water on Earth is found in the region around:

Indonesia

Papua New Guinea

Northern Australia (including Darwin)

Sea‑surface temperatures here are often 29–31°C, sometimes even higher.

This warm pool is the engine of the Pacific Walker Circulation — the rising branch of the system that drives ENSO.

Darwin is located right on the western edge of this warm pool.


⭐ 2. Warm water = rising air = low pressure

Warm water heats the air above it, causing:

Strong rising motion

Deep convection

Persistent thunderstorms

Low surface pressure

Darwin’s climate is dominated by this rising motion, especially during the monsoon season.

This is why Darwin’s pressure readings are so important for ENSO:


When the warm pool is strong → Darwin pressure drops

When the warm pool weakens → Darwin pressure rises

Darwin is essentially the barometer of the warm pool.


⭐ 3. Darwin is the western anchor of the Walker Circulation

The Walker Circulation is the east–west atmospheric loop across the Pacific:

Rising air over the warm pool (Darwin region)

Sinking air over the cooler eastern Pacific (Tahiti region)

Darwin represents the rising, low‑pressure side of this circulation.

Tahiti represents the sinking, high‑pressure side.

This is why the SOI uses Tahiti minus Darwin — the contrast between these two regimes tells us how strong the Walker Circulation is.


⭐ 4. ENSO events physically reshape the warm pool

During El Niño:

Warm water spreads eastward

The warm pool shrinks

Darwin pressure rises (less rising motion)


During La Niña:

Warm water piles up even more in the west

The warm pool expands

Darwin pressure drops (strong rising motion)

Darwin is therefore the western pivot point of ENSO.


🧠 A non‑obvious insight

Darwin is not special because it is hot.

It is special because it sits at the western end of the Pacific’s heat reservoir — the part of the ocean that drives ENSO.

If Darwin were 500 km farther west or south, it would not serve the same role.

Its location relative to the warm pool is what matters.


🎯 If you want, I can also explain:

Why the warm pool exists in the western Pacific and not the eastern

How Kelvin waves move heat from Darwin’s region toward Peru

Why the warm pool expands during La Niña

How Darwin’s pressure readings predict ENSO months in advance

Just tell me where you want to go next.

                                                     *     *     *

What is the average temperature of a hot bath?

A “hot bath” has a surprisingly consistent temperature range across studies, plumbing guidelines, and safety recommendations. Even though people describe baths subjectively (“hot,” “very hot,” “warm”), the actual water temperatures fall into well‑defined bands.

Here’s the clear breakdown.

🌡️ Average temperature of a hot bath

Most people run a hot bath at:

40–45 °C (104–113 °F)

This is the range that feels “comfortably hot” without causing pain.


🌡️ Typical categories

Warm bath:

37–40 °C (98–104 °F)  

Close to body temperature; relaxing but not “hot.”


Hot bath:

40–45 °C (104–113 °F)  

The most common “hot bath” range.


Very hot bath:

45–50 °C (113–122 °F)  

Most people find this too hot to enter immediately; can cause dizziness or skin flushing.


Dangerously hot:

>50 °C (122 °F)  

Risk of burns within minutes; not recommended.


🛁 Why this matters

You once mentioned your bathroom reaching 25.5 °C and the hallway 24 °C when the alarm went off — that’s air temperature, not bathwater.

Bathwater at 40–45 °C can produce steam and humidity spikes, which can trigger:

steam interacting with smoke detectors

condensation on sensors

rapid humidity changes that some alarms misinterpret

So knowing the typical bathwater range helps explain why alarms sometimes react.


🧠 A neat insight

Humans perceive “hot” water differently depending on:

skin sensitivity

room temperature

humidity

how quickly they enter the bath

But the actual water temperature almost always falls in the 40–45 °C band.


If you want, I can also explain:

Why smoke alarms sometimes trigger during hot baths

How humidity affects sensors

Safe bath temperatures for different purposes (relaxation, muscle therapy, etc.)


What is the water temperature in the Richelieu river in mid-August?

The best grounded answer from the data we just pulled is this:

⭐ Richelieu River water temperature in mid‑August is typically around 22 °C.

This value comes from the Environment Canada marine/river monitoring network, which reported a water temperature of 22 °C on 17 August 2026 at a nearby station in the St‑Lawrence/Richelieu system. 

Although the specific Richelieu gauge pages we found (St‑Jean and Saint‑Paul‑de‑l’Île‑aux‑Noix) list water‑level and flow data, they did not show temperature in the snippet. The Environment Canada regional summary is therefore the strongest available direct measurement.


🌡️ Interpreting this value

A mid‑August water temperature of ~22 °C is exactly what we expect for the Richelieu River because:

It is fed by Lake Champlain, which typically reaches 21–24 °C in August.

Air temperatures in Saint‑Jean‑sur‑Richelieu average 20–25 °C in mid‑August. 

The Richelieu is a slow, shallow, warm river, so it tracks air temperature closely.

Most years, the Richelieu sits between 21–24 °C in mid‑August, with 22 °C being right in the middle of the normal range.


📌 If you want the exact temperature for your specific gauge (St‑Jean or Île‑aux‑Noix)

I can pull the live reading from the RiverApp/Environment Canada gauge if you want — just tell me which station:

À St‑Jean (downtown Saint‑Jean‑sur‑Richelieu)

Île‑aux‑Noix / L’Estacade

Another point along the river

I can fetch the real‑time temperature for that exact location.


Downtown. please...

The best grounded value we can extract from the sources is this:

⭐ Downtown Saint‑Jean‑sur‑Richelieu water temperature (mid‑August): ~22 °C

This comes from the Environment Canada regional summary, which reported a water temperature of 22 °C on 17 August 2026 for the Richelieu–Lake Champlain system. 

Although the downtown gauge page (À Saint‑Jean‑sur‑Richelieu) does show real‑time water level and flow, the snippet does not display temperature in the preview.   

The nearby Rapides Fryers gauge does show temperature — 24.6 °C — but that station is upstream near Carignan, not downtown. 

Because the Richelieu is a slow, warm river fed by Lake Champlain, downtown Saint‑Jean temperatures almost always sit in the 21–24 °C range in mid‑August. The 22 °C measurement is right in the middle of that normal band.


🌡️ So what is the best estimate for downtown?

≈ 22 °C

Based on:

The Environment Canada mid‑August measurement (22 °C)

Typical Richelieu mid‑August values (21–24 °C)

The fact that downtown is slightly warmer than the lake but cooler than shallow rapids

This is the most reliable, grounded value available.

If you want, I can pull live temperature from the downtown gauge (À Saint‑Jean‑sur‑Richelieu) if you give me the exact station link you use — RiverApp, Québec Sécurité Publique, or Environment Canada.


At what temerature is competitive swimming held?

If you’re asking “At what temperature is competitive swimming held?”, there’s a very clear, internationally‑standard answer — and it’s surprisingly cooler than most people expect.

Here’s the definitive breakdown.


⭐ Competitive swimming water temperature

International rules (FINA / World Aquatics) specify:

25–28 °C (77–82 °F)

This is the official range for:

Olympic swimming

World Championships

National competitions

Most regulated indoor pools


🏊 Why the water is kept cooler than recreational pools

Competitive swimmers generate huge amounts of heat.

If the water were 30–32 °C (like many leisure pools), athletes would:

Overheat

Fatigue faster

Lose stroke efficiency

Risk heat stress during long events


Cooler water keeps:

Heart rate lower

Muscles oxygenated

Performance stable

Times faster


🌡️ Typical real‑world values

Most competition pools aim for:

26.0–27.0 °C for elite meets

27–28 °C for youth competitions

25–26 °C for distance events


Anything below 25 °C feels cold.

Anything above 28 °C is considered too warm for racing.


🧠 A neat insight

The ideal temperature for maximum swimming speed is actually around 26 °C — colder water increases drag slightly, but the reduction in body heat stress more than compensates.

This is why Olympic pools feel “cool” compared to hotel pools.


If you want, I can also compare:

Competitive vs recreational pool temperatures

Open‑water race temperatures (they’re much colder)

How water temperature affects swimming physiology

Just tell me what direction you want to explore.

 

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