332
June 2018
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
PHOTOGRAMMETRIC ENGINEERING
& REMOTE SENSING
J
ournal
S
taff
Publisher ASPRS
Editor-In-Chief Alper Yilmaz
Technical Editor Michael S. Renslow
Assistant Editor Jie Shan
Assistant Director — Publications Rae Kelley
Electronic Publications Manager/Graphic Artist Matthew Austin
Photogrammetric Engineering & Remote Sensing
is the official journal of the
American Society for Photogrammetry and Remote Sensing. It is devoted to the
exchange of ideas and information about the applications of photogrammetry,
remote sensing, and geographic information systems. The technical activities of
the Society are conducted through the following Technical Divisions: Geographic
Information Systems, Photogrammetric Applications, Lidar, Primary Data
Acquisition, Professional Practice, and Remote Sensing Applications. Additional
information on the functioning of the Technical Divisions and the Society can
be found in the Yearbook issue of
PE&RS.
Correspondence relating to all business and editorial matters pertaining to this
and other Society publications should be directed to the American Society for
Photogrammetry and Remote Sensing, 425 Barlow Place, Suite 210, Bethesda,
Maryland 20814-2144, including inquiries, memberships, subscriptions, changes
in address, manuscripts for publication, advertising, back issues, and publica-
tions. The telephone number of the Society Headquarters is 301-493-0290; the
fax number is 301-493-0208; web address is
.
PE&RS
.
PE&RS
(ISSN0099-1112) is published monthly by the American Society
for Photogrammetry and Remote Sensing, 425 Barlow Place, Suite 210, Bethesda,
Maryland 20814-2144. Periodicals postage paid at Bethesda, Maryland and at
additional mailing offices.
SUBSCRIPTION
.
For the 2018 subscription year, ASPRS is offering two options to
our
PE&RS
subscribers —an e-Subscription and the print edition. E-subscribers
can plus-up their subscriptions with printed copies for a small additional charge.
Print subscriptions are on a calendar-year basis that runs from January through
December. Electronic subscriptions run for twelve months on an anniversary
basis. We recommend that customers who choose both e-Subscription and print
(e-Subscription + Print) renew on a calendar-year basis. The new electronic
subscription includes access to ten years of digital back issues of
PE&RS
for
online subscribers through the same portal at no additional charge. Please see
the Frequently Asked Questions about our journal subscriptions.
The rate of the e-Subscription (digital) Site License Only for USA and Foreign:
$1000.00; e-Subscription (digital) Site License Only for Canada*: $1049.00;
Special Offers: e-Subscription (digital) Plus Print for the USA: $1,365.00;
e-Subscription (digital) Plus Print Canada*: $1,424.00; e-Subscription (digital)
Plus Print Outside of the USA: $1,395.00; Printed-Subscription Only for
USA: $1065.00; Printed-Subscription Only for Canada*: $1,124.00; Printed-
Subscription Only for Other Foreign: $1,195.00. *Note: e-Subscription/Printed-
Subscription Only/e-Subscription Plus Print for Canada include 5% of the total
amount for Canada’s Goods and Services Tax (GST #135123065).
POSTMASTER
.
Send address changes to
PE&RS
, ASPRS Headquarters,
425 Barlow Place, Suite 210, Bethesda, Maryland 20814-2144. CDN CPM
#(40020812)
MEMBERSHIP
.
Membership is open to any person actively engaged in the practice
of photogrammetry, photointerpretation, remote sensing and geographic
information systems; or who by means of education or profession is interested
in the application or development of these arts and sciences. Membership is
for one year, with renewal based on the anniversary date of the month joined.
Membership Dues include a 12-month electronic subscription to
PE&RS
. Or you
can receive the print copy of
PE&RS
Journal which is available to all member
types for an additional fee of $60.00 USA and or $75.00 for international
shipping. Subscription is part of membership benefits and cannot be deducted
from annual dues. Dues for ASPRS Members outside of the U.S. will now be the
same as for members residing in the U.S. Annual dues for Regular members
(Active Member) is $150; for Student members it is $50 for USA and Canada;
$60 for Other Foreign. A tax of 5% for Canada’s Goods and Service Tax (GST
#135123065) is applied to all members residing in Canada.
COPYRIGHT 2018.
Copyright by the American Society for Photogrammetry and
Remote Sensing. Reproduction of this issue or any part thereof (except short
quotations for use in preparing technical and scientific papers) may be made
only after obtaining the specific approval of the Managing Editor. The Society
is not responsible for any statements made or opinions expressed in technical
papers, advertisements, or other portions of this publication. Printed in the
United States of America.
PERMISSION TO PHOTOCOPY.
The appearance of the code at the bottom of the
first page of an article in this journal indicates the copyright owner’s consent
that copies of the article may be made for personal or internal use or for the
personal or internal use of specific clients. This consent is given on the condi-
tion, however, that the copier pay the stated per copy fee of $3.00 through the
Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, Massachu-
setts 01923, for copying beyond that permitted by Sections 107 or 108 of the
U.S. Copyright Law. This consent does not extend to other kinds of copying,
such as copying for general distribution, for advertising or promotional purpos-
es, for creating new collective works, or for resale.
The increasing sunlight and warmth of springtime provoke buds and blooms amidst
the trees, flowers, and grasses on land. Warm air and sunlight also beget warmer
ocean waters and provoke blooms of the “grass of the sea”—phytoplankton. These
tiny, plant-like organisms float near the ocean surface and turn sunlight and carbon
dioxide into sugars and oxygen. In turn, they become food for the grazing zooplankton,
shellfish, and finfish of the sea.
On May 5, 2018, the Operational Land Imager (OLI) on Landsat 8 acquired a natural-
color image (top) of a phytoplankton bloom in the North Sea. The next day, the Moderate
Resolution Imaging Spectroradiometer (MODIS) instrument on NASA’s Aqua satellite
observed the same bloom in a wider context. Five days earlier, MODIS detected visible
plumes of sediment moving through the area to the west.
The milkier, lighter-colored waters are probably filled with coccolithophores, while
greener areas may be diatoms. (It is impossible to know for sure without direct water
samples.) The brightness of the color may reflect the density of the phytoplankton,
while the various swirls and shapes trace the intricate movements of currents, eddies,
and tides.
Phytoplankton are most abundant in the North Sea in late spring and early summer
due to high levels of nutrients in the water. Melting sea ice and increased runoff from
European rivers—a product of melting snow and spring rains—carry a heavy load of
nutrients out to sea, while also freshening the surface waters. Intense seasonal winds
blowing over the relatively shallow sea also cause a lot of mixing that brings nutrients
to the surface.
In a study published in August 2017, a research team from the United Kingdom found
that primary production in the North Sea has declined since the late 1980s. The
causes for less phytoplankton abundance are not entirely clear, but they appear to
be related to decreased nutrients—thanks to less runoff from European farms and
cities—increasing sea temperatures, and changing light levels. Whatever the cause,
the decrease in primary production has coincided with a decrease in zooplankton and
some higher forms of marine life that consume phytoplankton. At the same time, many
fish stocks remained stable, probably due to better fisheries management amid the
changing ocean conditions.
For more information, visit
NASA Earth Observatory images by Joshua Stevens, using Landsat data from the U.S.
Geological Survey and MODIS data from LANCE/EOSDIS Rapid Response. Story by
Mike Carlowicz.
