Mangroves are many species of tree adapted to living in salty water along coastlines and tidal rivers not far from the equator. They are remarkable in many ways and confer a host of benefits to their habitats. Here are some significant ones.

Mangroves and mangrove habitats play a major role in protecting coastal settlements from storm surges and waves. Mangroves significantly reduce the energy of waves, lowering wave height inland, including from tsunamis, and reduce surges from tropical storms. We took a boat through the mangroves in Southern Vietnam once, and it was an eye-opening maze of channels and islands. I could see how they act like a natural breakwater.

Mangroves help stabilise land from erosion. This helps plants and fauna inland make their homes. Mangrove root systems also trap sediment brought downriver or from the sea, building their environment and creating peaty soil when they decay.

Their incredible prop root network creates a wonderful sheltered space for marine wildlife to grow and develop. The nooks and crannies help protect young from predators until they are older and can better fend for themselves. This protective environment increases populations and helps local fishers and communities. The calm and sheltered waters inside mangrove habitats also provide sanctuary for birds and a host of other non-marine wildlife.

Mangroves are an excellent carbon sink. They capture carbon as they grow, and the low-oxygen sediments deposited beneath them help lock carbon away.

I've contributed to plant trees through Eden Projects with a portion of any monthly or one-off support I receive. I wanted to explain Mangroves partly because, as of July 2023, together, we've passed 26,000 trees planted, most in mangrove restoration projects in Madagascar, and provided over 350 work days for locals.

"Madagascar is one of the world's top biodiversity conservation priorities because of its endemic species and severe habitat loss rates. Restoration in Madagascar is important because the destruction of the mangrove estuaries along the coastline has caused mudflats to wash into the ocean, destroying once-productive fisheries and increasing the vulnerability of coastal communities to hurricanes, tsunamis, and floods. In the dry deciduous forests, deforestation threatens one of the world's rarest and most diverse forest systems."

Mangroves make a real difference. To everyone who's helped make this happen, thank you!

Mangroves

Redshift refers to light being 'shifted' towards the redder end of the spectrum — longer wavelengths — as objects move away from each other. If a light source is moving towards us then light is blueshifted, shifting towards the bluer end of the spectrum, shorter wavelengths.

Imagine waving a spring back and forth to create a wave and then starting to run away – the waves would be stretched longer. Because the universe is expanding 🤯 distant galaxies are moving away from us faster than nearer ones — imagine how the chocolate chips in a cookie move away from each other as the cookie bakes and grows in an oven. By comparing the redshift of light seen from distant galaxies with what we would expect to see it's possible to use redshift to determine how far they are away.

Redshift is an example of the Doppler effect, or Doppler shift, in action. It's more commonly known by the stretching or compressing of soundwaves as, say, an ambulance moves towards or away from you, or how the sound in front of a moving aircraft eventually can produce a sonic boom.

Redshift

The Doppler effect is the change in frequency of a wave as its source moves relative to the observer. The same effect that causes the change in pitch of a siren as it drives past is also used to estimate blood flow with ultrasound, measure the speed of a passing car, and even determine the motion of the stars. Doppler shift-based satellite navigation was also the first operational use of a system that eventually led to GPS.

When a siren or similar approaches I try to imagine the crunching up of the sound waves — the vehicle seemingly chasing after its own sound — and the stretching out of the waves as it heads past and into the distance. At least it makes it less painful on the ears.

The Doppler Effect

The often lovely line of interesting seaweed, driftwood and things to find left behind by the waves at the top of high tide. Hopefully, not too much plastic.

More lines: browse line, plimsoll line. draw smooth lines. choose the fast line, the coastline paradox

More beaches: surfing breaks, beaches—amazing for play, gastropods, sea jelly—sea star.

Strand line

Surfing breaks: Beach, reef and point

The anatomy of a wave showing the key features of a wave: the crest, amplitude, trough, wavelength and when and how it starts to break on a beach.

Common in experience. Less commonly understood.

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Category: waves