UAE Weather: Monster fog facts kids will love

WHAT IS FOG? Fog is a type of low-lying cloud made out of tiny water droplets. It is different from clouds because it is closer to the ground rather than up in the sky, and it is different from mist because it is thicker and makes it harder for you to see (by definition fog reduces visibility to less than 1km, whereas you can see through mist more easily).

WHY DOES FOG HAPPEN? Fog forms when the dew point and the air temperature difference is less than 2.5 degrees C. It begins to form when water vapour condenses into tiny water droplets that stay hanging in the air. It happens in the UAE when cold winter weather like we are experiencing now is coupled with high humidity levels close to 100%. When this is combined with wind speeds no higher than 5km/h and high-pressure cooling of the Earth’s surface, you get the thick fog we have seen this year.

WHY IS FOG WHITE? Fog is white because light from the sun is white, and the water droplets that form fog do not absorb light. This means they reflect the light equally at all wavelengths, making it appear white. By comparison, air particles reflect the wavelength of blue light more strongly than other colours, which is why the sky appears blue.

WHY IS IT CALLED MONSTER FOG? This is a nickname of the very dense fog that we sometimes experience in the UAE. It gets its scary-sounding name because thick fog reduces your ability to see very far, which can be especially dangerous for those driving on the roads. It’s important that if there is fog on the roads that motorists drive very carefully and put their strong fog lights on.

WHERE DOES FOG FORM? Fog happens in countries all over the world, and there are many different types of fog that occur in different weather conditions. Fog is very common near large bodies of water (like the sea in the UAE’s case) and valleys.

WHAT HAPPENS IF YOU BREATHE FOG? Fog in itself is not bad for your health – breathing fog is just like breathing in water particles from the air. However smog is formed when fog mixes with smoke and other pollutants, and this can sometimes cause health problems.

WHAT CAUSES FOG IN THE UAE? In the UAE, fog tends to originate from the desert and the western areas, mainly Al Ain and Abu Dhabi. As the fog’s density increases, it expands and covers other parts of the country as it moves towards Dubai.

WHAT ARE THE DIFFERENT TYPES OF FOG? There are 10 types of fog. The most common form of fog is radiation fog, which occurs when the Earth’s surface cools the humid air above it at night time. When water vapour from the sea gets cooled in this way it ‘condenses’ into tiny water droplets that stay hanging in the air. This sort of radiation fog dissolves soon after sunrise. Other types of fog include Ground Fog, Advection Fog, Precipitation Fog, Ice Fog and Steam Fog.

IS FOG DANGEROUS? Fog can make it dangerous to drive a car because it reduces your ability to see very fair in front of you. It is important to put on your fog lights and to drive slowly and carefully if you are driving in foggy conditions.

WHERE IS THE FOGGIEST PLACE ON EARTH? Although it may seem like we’ve been having a lot of foggy days recently, the UAE is not a particularly foggy place. Newfoundland, in Canada, is known to be the world’s foggiest place, usually experiencing more than 200 days of thick fog every year.

HOW DOES FOG GO AWAY? As the air heats up again during the day, fog will slowly disappear as the tiny water droplets turn again to a gas in the form of water vapour.