Image for “Earlier bird migration”

Addition to http://envnatres.wordpress.com/2013/11/13/earlier-bird-migration/

Earlier bird migration

An interesting study by University of East Anglia (and University of Iceland, Tomas G Gunnarsson) found that individual (adult) birds are not migrating earlier, rather, since they nest earlier, the young birds migrate earlier.

So warming climate is allowing the birds to nest and hatching earlier, which results in those younger birds arriving earlier – but apparently, each individual bird will stick to a fixed date for migration.

Or, as it says in the news item:

We found that birds hatched in the late 1990s arrived in May, but those hatched in more recent years are tending to arrive in April. So the arrival dates are advancing because the new youngsters are migrating earlier.

This was found by studying the Icelandic black-tailed godwits over 20 years.

About this study on Eurekalert.com.

Dust storm 12 Nov

Image courtesy of NASA/Rapidfire, obtained via IMO.

Satellite image from 13:10 on 12 November.

Small dust storm visible from the SA of Iceland

Small dust storm visible between the clouds in the SA of Iceland.

Image courtesy of NASA/Rapidfire via IMO.

Satellite image from 13:15 today, 8 November 2013.

Particulate matter in Reykjavik and Hafnarfjörður on 1 Nov 2013

Relatively high levels of particulate matter were measured in Reykjavik and Hafnarfjörður on 1 November 2013. The situation was unusually complicated, low wind, some dust storm seen and a burning ship in Hafnarfjörður.

Let's start with a satellite taken at around 13 on 1 Nov. A clear dust storm is seen blowing off the Reykjanes peninsula. There also seems to be a dust cover in Reykjavik, but cloud cover makes it impossible to distinguish, and the source area is hidden.

Satellite image taken at 13:10 on 1 November. Image courtesy of MODIS/Rapidfire.

It is not obvious where the source area is?

The wind direction in Reykjavik was northerly, like can be seen from the data from IMO below. The wind speed increased around noon, but still not very strong winds.

Data from the IMO (vedur.is).

Due to the northerly wind direction, the most likely source areas, if there was a dust storm, are south of Langjökull.

There were high levels of PM in Reykjavik and Hafnarfjörður, and since they are similar it might be a dust storm.

Measurements of PM at Grensásvegur on 1 Nov.

Traffic seem to be the most likely reason for the high levels of PM in the morning, and possibly for the whole day. There might also be a contribution from dust storm …

NOx reaches high levels in the morning, therefore likely traffic in the morning. However, not very high in the afternoon, so possibly something else, such as dust storm.

Measurements of PM form Hvaleyrarholt, Hafnarfjörður, 1 November.

In the morning, and possibly also just after noon, it was the burning of the ship Fernando which caused the high levels of PM. Also might be a dust storm contribution in afternoon.

The Icelandic coast guard ship, Thor, putting out the fire. mbl.is/Júlíus Sigurjónsson (fréttin).