Nazi scum

Plot Against America captures a terrifying aspect of Nazism that Hunters misses

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Sunday Scaries

Psychologists say it’s time to rethink the “mental health day

There are two steps that companies can take to help their employees' mental health.

Jutta Kuss/Getty Images

While improvements are being made, discussing mental health is still taboo. That makes it difficult to ask for a “mental health day” — a day that allows you to address mental health issues, whether those be anxiety, burnout, or depression, in a space away from work.

Many Americans are too nervous to ask for a sick day when they are physically ill, let alone ask for one when they feel mentally unwell. That, experts say, is a reality that should change.

Tom Bailey and Faith Pizzey

Mind and Body

why people sweat in the winter: 4 explanations

Sweating is usually the body’s way of stopping you from overheating.

Koldunov/Shutterstock

If you’re hot and sticky even before your daily commute, you might ask why you sweat so much.

Sweating is usually the body’s way of stopping you from overheating. But for some people, sweating becomes a problem. Either they sweat for no obvious reason or (as Prince Andrew admitted last year) not at all.

So why do some people sweat more than others? And what can you do about excess sweating?

Remind me again, why do we sweat?

Humans need to regulate their internal body temperature to keep it constant, even when the environmental temperature rises, perhaps on a hot day, sitting in a hot-tub or running for the bus.

That’s because a rise in internal body temperature can lead to our organs overheating, fatigue, heat exhaustion and heatstroke.

Preventing severe heat gain requires a careful balance between the heat our body produces (from everyday metabolism), heat from the environment and the heat our body loses.

Our bodies are well-designed for this. We have special temperature sensors in our skin and central nervous system (brain and spinal cord) that send signals to the body’s thermostat in the brain to alert it to increases in body temperature.

The body’s largest organ, the skin, is also designed to remove heat from the body. The most noticeable way is losing heat via evaporating sweat.

How does sweating cool us down?

When our skin or core body temperature rises sufficiently, the thermostat in the brain sends impulses via our central nervous system to increase blood flow to the skin. The thermostat also activates the sweat glands.

Our sweat glands release droplets onto our skin that become vapor when the blood flowing through the skin passes underneath.

As the sweat vaporizes, energy (in the form of heat) passes into the environment, cooling the blood. This cooled blood gets circulated back to the heart and brain so it cools our core body temperature.

The body loses excess heat via evaporation.VectorMine/Shutterstock

This is why a day in the sun can feel so draining. Your body is working much harder and using much more energy to keep you cool.

By preventing our organs from overheating, sweat not only keeps us healthy, it also allows us to enjoy (or tolerate) the hot Australian summer.

So it’s important to stay hydrated on a hot day so your body can produce and replace the volume of sweat necessary to keep you cool.

OK, but why do I sweat so much?

You might find yourself sweating more or less than usual for a number of reasons, other than it being a hot day.

4. Exercise

Exercise improves our ability to produce sweat and keep cool. People who exercise regularly (particularly in the heat) can produce more sweat during exercise. This helps our bodies perform longer, with less physiological strain.

Simon Boxall and Abiy S. Kebede

Future vacation

Half of the world’s sandy beaches could disappear in 80 years

Researchers had previously analyzed satellite images showing shoreline change from 1984 to 2016.

R.M. Nunes/Shutterstock

Up to half of the world’s sandy beaches are at risk of disappearing by the end of this century if no action is taken to limit greenhouse gas emissions. That’s according to a new study, published in Nature Climate Change. Even assuming a better outcome for action on climate change, where global emissions peak around 2040, well over one-third (37%) of the world’s beaches would be lost by 2100.

Researchers had previously analyzed satellite images showing shoreline change from 1984 to 2016. They found that a quarter of sandy beaches worldwide had already eroded at a rate of more than 0.5m per year, shedding over 28,000 square kilometers of land to the sea.

The rate at which sea levels are rising is accelerating by about 0.1mm per year each year. But sea-level rise won’t be even across the globe. The term “sea level” can be misleading – the sea surface is not flat. Much like the atmosphere, it has high and low-pressure areas that create mounds and troughs. Some of these are created by major currents, so changes that will take place as the oceans warm will change the topography of the sea surface. Some areas will receive less than the predicted average sea level rise, but many will see more.

More than 60% of sandy beaches in Gambia and Guinea-Bissau may be lost to erosion by rising seas, while Australia is expected to lose nearly 12,000 km of sandy coastline. For small island states such as Kiribati, the Marshall Islands and Tuvalu, losing 300m of land – as predicted for some – would be catastrophic.

An aerial view of Funafuti atoll, Tuvalu, shows the airstrip of Vaiaku international airport. There is little space for the coast to retreat as sea levels rise.maloff/Shutterstock

Nowhere to go

Sandy beaches occupy more than one-third of the global coastline and of all the different types of beaches, sandy beaches are the most heavily used by people. Many coastal areas have been built on, for industry, housing and tourist resorts.

These “softer” parts of the shoreline have always been at the mercy of ocean storms and the tides. But the predicted sea-level rise on top of these daily inundations pushes the boundary between the coast and sea inland, a process known as a coastal retreat.

The build-up of people and concrete at the landward fringe of sandy beaches has created an abrupt barrier to coastal retreat, preventing beaches from moving inland as sea levels rise. Instead, sandy stretches of coastline are at risk of being eroded and washed away entirely.

Warming seas also promise more intense and frequent storms, which are capable of moving entire beaches overnight. Porthleven Beach in Cornwall, UK lost all of its sand during a storm in January 2015, to be returned by the tide a few days later.

Soft sandy beaches are continuously moved by waves and currents – depleting them in certain areas and depositing them in others. This transport of sand is normal, but the combined force of higher sea levels and stronger storms could spell extinction for many beaches.

All of this is very worrying for the millions of people who call these regions home. The world’s sandy coastlines tend to be densely populated, and are becoming more so over time. In other research, it was found that sea-level rise by 0.8m could erase 17,000 square km of land and force up to 5.3 million people to migrate, with an associated cost of USD$300-1,000 billion globally. In Africa alone, up to 40,000 people per year could be forced to migrate due to land loss by coastal erosion if no adaptive measures are in place by 2100.

But it isn’t just climate change. Humans are actively accelerating coastal erosion by removing sand from beaches in enormous quantities and at much faster rates than they can be naturally renewed. Gravel and sand is extracted from rivers and on beaches for use in construction – and at a faster rate than fossil fuel extraction in some areas.

Coastal ecosystems that bind and trap sediment, like mangrove swamps, are also being destroyed. The world lost almost 10,000 square kilometers of these habitats between 1996 and 2016. Meanwhile, sediment supply to the coast is also affected by building dams and irrigation systems upstream.

Mangroves are effective buffers against storms and help trap more sand around the coast.Ibenk_88/Shutterstock

Sea level rise is inevitable, but how bad it will be is still not certain. Replenishing the most endangered beaches by pumping sand onto them – a process called “coastal nourishment” – could cost USD$65–220 billion in total, but that’s still less than one-fifth of the economic cost of taking no action at all on sea-level rise. It could reduce land loss by up to 14%, lower the number of people that might be forced to migrate by up to 68%, and shrink the cost of forced migration by up to 85% by 2100.

Shireen Kassam

Many of the important benefits of a plant-based diet – particularly for climate health and animals – are well known. Yet despite the science being very clear, there remains confusion about the impact on human health.

We have long known for example, that a diet centered around whole plant-foods – fruits, vegetables, whole-grains, beans, nuts and seeds – significantly reduces the risk of heart disease, type 2 diabetes, obesity and certain cancers. In fact, a low-fat plant-based diet is the only diet to have been shown to actually reverse established coronary artery disease. It has also been seen to reverse type 2 diabetes, enable effective and sustained weight loss without portion control or exercise, and arrest the progression of early-stage prostate cancer.