Flash-to-bang method

Two hikers look at distant lightning and count how long it takes to hear the thunder to estimate how far the lightning is away

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How far away is the storm? The flash-to-bang method can help.

When lightning is made by a storm the rapid heating and expansion of the air create the thunderclap. But because sound travels slower than light, there's a gap between seeing the lightning and hearing the thunder it produced. Using Distance = speed x time, by counting the seconds from seeing the lightning you can easily estimate how far away it is.

Conveniently, the speed of sound in air is about 330 metres/second. So depending on your unit preference:

every 3s you wait the thunder travels about 1 km
every 5s you wait the thunder travels about 1 mile

Give it a try at a safe distance from your next lightning storm.

Also see: thunderclap or rumble, thunder clouds, dirty thunderstorm

Published 31 Jul 2022

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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. Protect 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. Stabilise 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. Nurture 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. Sequester 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. As Eden Projects explain: "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 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. Protect 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. Stabilise 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. Nurture 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. Sequester 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. As Eden Projects explain: "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!

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