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THE POLAR REGIONS OF THE EARTH AND MARS – SOME DIFFERENCES IN THE
RADIATION HEAT BUDGET
O.N. Abramenko, I.A. Komarov, V.S. Isaev
Lomonosov Moscow State University, Faculty of Geology, Geocryological Department, 119991
Moscow, Leninskie Gory, bldg. 1,
oleg_abramenko@inbox.ru, ilya_komarov@mail.ru, tpomed@rambler.ru
Abstract: The time and space radiation heat patterns have been investigated at five polar Antarctic sites
(Novolazarevskaya, Molodezhnaya, Bellinshausen, Mirny, and Vostok). Similar variability appears in data from Mars polar
ice caps. The reported comparative analysis allows evaluating the contributions from different thermophysical components
of the radiation heat budget in the Antarctic and Mars high-latitude regions.
Key Words: Antarctica, Mars, radiation-heat balance, cryogenic conditions, comparative analysis.
Introduction
The study has focused on comparing
quantitative and qualitative parameters that
represent the radiation heat budget in
Antarctica and in polar Mars. Mars is a planet
with a thin atmosphere, a thick cryosphere, and
permanent ice caps at both poles. There is the
Antarctic on the Earth, which is similar to the
Mars high-latitude regions, especially to the
northern cap consisting mostly of water ice;
similarities are the surface areas and the ice
sheet thicknesses (tab. 1). The Antarctic
climate is the most severe (the coldest natural
temperature ever recorded on Earth was –
89.2 °C at the Vostok station) and the least
affected by anthropogenic loads.
We analyzed records from five Antarctic
stations (Novolazarevskaya, Molodezhnaya,
Bellinshausen, Mirny, and Vostok) collected by
the Arctic and Antarctic Research Institute
from the start of observations (1958–1971)
through 2008–2009 (till 1992 at
Molodezhnaya). The stations are located on or
near the shore, or in the continent interior on
ice or within Antarctic oases (fig.1). The
inventory consisted of the following data:
(1) long-term average solar flux during
selected observation periods (at clear sky, with
cloud amounts less than 2, and at up to 10);
(2) statistically processed data on
monthly and yearly totals of the radiation
budget components;
(3) statistically processed data on
monthly and yearly totals of direct beam solar
radiation at normal incidence and atmospheric
clearness index .
Figure 1. Russian stations in Antarctic. Active:
Bellingshausen, Mirny, Novolazarevskaya,
Vostok, Progress. Closed: Molodeznaya,
Druznaya-4, Leningradskaya, Russkaya, Soyuz.
Study methods on example of
Novolazarevskaya station
As part of the 53rd Russian Antarctic
Expedition, one of us [Abramenko, 2009] set up
a test station at the Novolazarevskaya site, in
the Schirmacher oasis located 80 km far from
the northern Antarctic coast in the central
Queen Maud Land.
Oleg Abramenko selected a 100 × 100 m
frost area covered by loose sediments as a site
for research, for studying the thickness of the
seasonally thawed layer, determination of the
value of the heat conductivity coefficient, and
measurement of the components of the
radiation–heat balance. The coordinates of the
2
site (GPS) are 70°46′20′′ S and 11°48′95′′ E.
The relative elevation of the site is 110 m
above sea level.
During the preparation period, the
equipment for determination of the main
parameters of the radiation–heat balance,
thermophysical properties of rocks, and so on
was chosen. The equipment was provided by
the Department of Cryology of the Moscow
State University. Moreover, sites for research
were selected and the method of research work
was proven.
Within the framework of the International
Polar Year, the present author selected the site
for measurement of the seasonal thawing depth
according to the CALM method’s instructions
[Brown et al., 2000]. This site is included in the
Unified World Database. In the future,
analogous measurements can be carried out at
this site with a different periodicity. At the site,
loggers provided by the University of Alaska
(USA) were established. The corners of the site
were marked with stakes and recorded in the
GPS. Measurements of the thawing depth were
performed at a grid with measurement points
10 m apart (a total of 121 measurements) at the
end of the thawing season. In all, three
measurements of the depth of the seasonally
thawed layer (STL) were performed at every
point. A sounding probe was manufactured of a
150 cm metal rod and marked every 10 cm.
The average thickness value of the seasonally
thawed layer at the site is 60–80 cm.
The main problem of geocryological
surveying is the study of the correlation
between the processes of formation and
evolution of seasonally frozen and permafrost
rocks, their temperature regime, and the
process of heat exchange between the
atmosphere and the upper layers of the
lithosphere. One quantitative characteristic of
the heat exchange is the radiative–heat balance
of the Earth’s surface. Understanding of the
structure of the radiative–heat balance and
variations in its components allows the
evaluation of the dynamics of the upper
boundary conditions, examining patterns of
formation and variations of the temperature
regime on the Earth’s surface, and determining
the character of evolution of cryogenic
processes. During the preparatory period, the
present author developed measurement
equipment [Abramenko, 2009].
The principle of operation of the method is
that an artificial heat source (sonde) is
introduced into the rock massif. It “perturbs”
the natural temperature field at a rate correlated
with the heat conductivity of the rocks. By
recording the relaxation rate of the temperature
field during the sampling, one can determine
the measured values of thermophysical
parameters (one or several), characterizing the
given kind of rock [Komarov, 2003]. For this
purpose, a cylindrical sonde was used. For
theoretical justification of the method of a
cylindrical sonde of a constant power, a
mathematical solution of the problem was used
concerning the heat distribution from an
infinitely thin and long source, sunk into a
homogenous isotropic medium emanating an
axisymmetrical heat flow of a constant power.
In the general case, the system of equations is
solved using a computer. However, in cases
where the heat capacity is regarded as constant,
which is the case during application of the
sonde in thawed and “low temperature” frozen
rocks, the system has an analytical solution.
At the stations Bellinshausen,
Novolazarevskaya, Molodezhnaya, Mirnyi, and
Vostok, the normal beam solar radiation was
from 33 to 56 % and dominated over other
radiation components that varied in the
following ranges: 6 to 26 % reflected, 3 to
23 % absorbed, 6 to 32 % scattered, and 9 to
17 % radiation on a horizontal surface (t
ab. 2). The estimated total annual heat
balance of the ice surface was negative, from
−20 to −40 W/m2.
Inside the domain there are zones with a
positive balance, such as oases, ice-free ridges,
and stationary water clearings. In oases, the
annual heat budget is 110 W/m2. The annual
totals of the radiation components range as
follows: normal beam radiation from 102 to
830 W/m2, horizontal radiation from 48 to
199 W/m2, scattered radiation from 67 to
179 W/m2, total radiation from 19 to
329 W/m2, and back radiation from 65 to
263 W/m2. The monthly means of climate
parameters at the selected stations were albedo
3
0.2–0.9, air moisture 48–90 %, wind speed 2.9–
13.4 m/s.
Methods of investigation of radiation-
heat parameters on Mars polar regions
Martian Climate Database (MCD) was used
for evaluation of temporal spatial mutability of
components of radiation-heat balance of the
surface, the surface temperature, and the
temperature of near-surface zone of atmosphere
for high latitude regions of Mars based on
General Circulation Model (GCM) - calculation
model of climate and atmosphere circulation.
This model is also widely used for weather
predicates and climate research on Earth.
The Martian version of GCM is the result of
cooperative work of LMD (Laboratoire de la
Meteorologie Dynamique du CNRS, LMD,
Paris) and AOPP (Atmospheric, Oceanic and
Planetary Physics, Department of Physic,
Oxford University, Oxford, England UK) and
are based on actual data received from orbital
stations and landing rovers Mars Pathfinder,
Mars global Surveyor, Viking 1, 2.
Influence of dustiness of atmosphere and dust
storms were taken into account adding some
corrections for different scenarios: “dust” year
and “clear” year, middle and strong global dust
storm. The database is an informative-
searching system equipped by calculation
module for the receiving data on climatic
parameters at present and during some periods
for precise site or region or all around the
planet.
The analyses of temperature conditions on
the surface and in the near-surface atmosphere
layers shows that dynamic of season
temperature have some characteristic features.
Maximal temperatures were observed at the
end of Martian summer while the warmest
season is fall (for North hemisphere).
Winter temperature tends to fall down with
some variations for different areas. It is the
coldest period for the area 64°N 48°Е with the
peak of negative temperatures coming to –
128.9°С.
Though the coldest time for more southern
areas 58°N 48°Е as well as for 64°N 30°Е is
spring with the temperatures around –123°С.
In the extremely cold period (Ls =330-360)
diurnal temperature fluctuates within 1 degree
for the area 65оN÷ 68 оN, within 50 degrees for
the latitudes 47оN and reaches the most
significant values up to 100 degree at the
latitude 43о N. Diurnal surface temperature for
latitudes 65 о N ÷ 68 о N come to its minimum
at 10 a.m. and maximum at 12 p.m. The lower
latitudes 43о N ÷ 47 о N are characterized by its
minimum at 8 a.m. while maximums are
differentiated according to the values of albedo.
The lowest temperatures on the Utopia area
(43oN 91oW), for example, were observed at
the mid-day, the highest – at 18 a.m. with 100
degree of temperature fluctuations. On the
areas with low albedo temperatures come to
minimum at 8 a.m., to maximum at 14-16 p.m.
varying within 40-50 degree.
The ranges of annual reflected radiation
generally for the Mars high latitudes are 414–
750 W/m2 for the northern ice cap and 532–
840 W/m2 for the southern ice cap. The
absorbed radiation ranges, respectively, as 658
to 2016 W/m2 and from 702 to 1539 W/m2. The
radiation data for the northern and southern
polar regions were processed on a space grid
for the coordinates 90°, 86.2°, 82.5°, 78.8°,
75° N and S; 135°, 90°, 45°, 0° W and 45°,
90°, 135°, 180° E to analyze annual cycles of
the surface and atmospheric infrared radiation,
absorbed and reflected radiation, and mean
monthly surface temperatures. Other
parameters were mean diurnal and monthly
temperatures of the surface and lower
atmosphere (5 m above the surface) estimated
for midnight and noon times and winter and
summer mean diurnal variations of wind speed.
The radiation heat budget components were
calculated with an equation used to process the
Earth’s ground surface data [Budyko, 1956].
Turbulent heat transfer was found as the
surface-air temperature difference (according to
MCD) multiplied by the heat transfer
coefficient. The latter was assumed to be 2–
5 W/(m2*K) proceeding from empirical data
obtained in laboratory at pressures and
temperatures typical of the Mars high latitudes
[Lebedev and Perelman, 1973]. The heat spent
for sublimation (ablimation) of CO2 or H2O ice
was evaluated from mean annual values of the
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process intensity obtained using GMCD. The
CO2 and H2O ice sublimation heat was
estimated with regard to its temperature
dependence [Komarov, 2003]. The heat flux
from the surface to the ice was calculated as a
solution to the thermal conductivity differential
equation at the respective boundary conditions.
The models included a two-layer section for the
northern ice cap and a three-layer section for
the southern cap [Komarov and Isaev, 2010].
Mean annual, seasonal, and diurnal
temperatures of the ground surface and
their variations
The mean ground surface temperature in the
insolated part of Mars at an average distance
from the sun is -43°C, and that averaged over
latitudes and seasons is -63°C. Like on the
Earth, the Mars ground temperatures vary as a
function of latitude and orography and have
diurnal and seasonal cycles with greater
contrasts than in the terrestrial temperatures.
The amplitude of diurnal temperature variations
on the equator reaches ~100°. The ground is
30–50° warmer than the atmosphere at 5 m
above the surface in the day time and is 5–7°
colder in the night.
Mid-latitude seasons in the northern and
southern hemispheres have different
temperature regimes because of the orbit
ellipticity.
In the same way as in the terrestrial high
latitudes, the sun does not set in summer and
does not rise in winter in the Mars polar
regions. Therefore, the ground temperatures are
maximum in summer and minimum in winter.
The summer and winter ground temperatures
vary, respectively, from -63° to -58°C and from
-138° to -128°C in the northern polar region;
the respective ranges in the south are from -43°
to -38°C and from -143° to -133°C (Komarov
et al. 2004).
It is noteworthy that Mars, with its low-
density atmosphere, cannot hold back the heat
that comes to the surface in the daytime and,
hence, a great amount of heat escapes to space
in the dark time (night and polar night). This is
the reason for large diurnal temperature
variations. In the most favorable conditions, in
summer daytime, air may be as warm as 293 K
(MCDB) in the insolated half of the planet, but
frost in winter nights may reach 148 K. The
lowest temperature at the southern ice cap is
113 K, the average being 155 K, which is
approximately the freezing point of carbon
dioxide at the atmospheric pressure on the Mars
surface. The lowest temperature of the northern
cap is 148 K.
It is important that, unlike the Earth, the Mars
surface temperature is due mostly to beam solar
heat rather than atmospheric heat transport
seeking to balance temperature contrasts. As a
result, the temperature may locally (on steep
slopes exposed to the sun) reach or even
slightly exceed 273 K, while the mean of the
north ice cap periphery (at 82° N) in the early
summer is 235 K (Ls = 90°).
The two hemispheres on Mars differ in
durations of the warm and cold seasons and in
temperatures controlled by their approaches to
the Sun; winters in the southern hemisphere are
longer and colder while summers are shorter
but warmer. Another feature of the cold season
(autumn and winter, Ls=210-300˚) is dust
storms and related climate change, which show
up in the dynamics of ice cap thickness.
Generally, the mean daily temperatures vary
over the year from 143.0 K to 272.7 K at the
south polar cap and from 147.4 K to 251.0 K in
the north.
The temperature regime of the uppermost
northern ice cap, where H2O ice locally
predominates, was modeled using the
HeatMars program for a one-layer subsurface
(Pustovoit 2005). Similar modeling for the
southern ice cap, which rather fits a two-layer
model and is seasonally dominated by CO2 ice
on the surface, was with the Teplo (“Heat”)
software (Khrustalev et al. 1994) (Fig. 2). The
heat capacities of H2O and CO2 ices in the
Martian conditions were obtained from
reference books.
The abrupt temperature change at the depth
25 сm (left) is due to the two-layer structure
with CO2 snow lying over H2O ice. The line
colors correspond to the months of the Martian
year.
Thermal conductivities were calculated from
known values of heat inertia and heat capacity.
The active layer thicknesses in the southern and
5
northern ice caps were estimated to be 12 to14
m and 24 to 26 m, respectively.
Figure 2. Monthly mean temperatures in the
southern (left) and northern (right) polar ice
caps along 180°. LS are solar longitudes
corresponding to months of the Martian year.
Conclusions
The components of the radiation heat
budget in the Earth’s Antarctic and Mars’s high
latitudes demonstrate qualitatively similar
patterns, but there is some difference in their
magnitudes. Namely, backscattered and
absorbed radiation is slightly lower on Mars
than at the Antractic Novolazarevskaya site
(Table 3). Unlike the Earth, the Mars surface
temperature is due mostly to beam solar heat
rather than atmospheric heat transport. As a
result, the temperature may be locally 272 K
while the mean of the north ice cap periphery in
the early summer is 235 K (Ls = 90°, where Ls
is solar latitude). Generally, the mean diurnal
air temperature at 5 m above the Mars surface
varies through a year from 143.1 to 249.9 K on
the southern ice cap and from 147.8 to 230.4 K
on the northern cap.
Acknowledgements
We greatly appreciate overall support by
V.V. Lukin, the head of Antarctic expeditions
at AARI (Arctic and Antarctic Research
Institute), as well as the aid of S.R. Verkulich,
the head of the 53rd Russian Antarctic
campaign, and the whole team of
Novolazarevskaya Station.
The study of Mars data was supported by
grants 04-05-65110 and 09-05-07045 from the
Russian Foundation for Basic Research.
References
Abramenko O.N., 2009. Methods for
investigating the surface radiation heat
budget components and thaw depths in
Schirmacher oasis (Antarctica). Vestn.
MGU, Ser. 4, Geol., No. 4, 67–69.
Brown J., Hinkel K.M., Nelson E.F., 2000. The
Circumpolar Active Layer Monitoring
(CALM) program: research designs and
initial results. Polar Geogr., 24 (3),
165–258.
Budyko M.I., 1956. Heat Budget of the Earth’s
Surface [in Russian]. Gidrometeoizdat,
Leningrad, 256 pp.
Komarov I.A., 2003. Termodynamics and
Heat-and-Mass Transfer in Permafrost
[in Russian]. Nauchnyi Mir, Moscow,
603 pp.
Komarov I.A., Isaev V.S., 2010. The Crylogy
of Mars and other Planets of the Solar
System [in Russian]. Nauchnyi Mir,
Moscow, 232 pp.
Lebedev D.P., Perel'man T.L., 1973. Heat and
Mass Transfer in Vacuum Sublimation
[in Russian]. Energiya, Moscow, 336
pp.
The Mars Climate Database. (http://www-
mars.lmd.jussieu.fr/).
6
Table 1. Ice parameters of Antarctic and Martian ice caps, compared
Area
Surface area,
km
2
Maximum ice
thickness, km
Ice
volume, km3
composition
Antarctic
1.4*107
4.8
26.7*106
H2O
Mars South Pole
cap
3.9*105
3.7
1.6*106
H
2
O and
mostly CO2
Mars North Pole
cap
6.8*105
2.0
1.4*106
CO
2
and mostly
H2O
Table 2. Radiation heat budget components at different Antarctic sites, compared
Site
Radiation
budget
Beam radiation
Solar radiation
Normal
Horizontal
total
backscattered
W/m2
Vostok
–6.7
344.7
105.0
147.8
111.8
Novolazarevska
ya
37.2
181.2
67.3
125.0
26.7
Molodezhnaya
38.6
144.5
62.8
134.0
50.5
Mirnyi
–8.5
148.2
62.4
135.3
108.1
Bellinshausen
20.2
42.2
20.7
7.8
45.2
7
Table.3. Annual means of heat-radiation budget components at sites of Martian poles and Antarctic Novolazarevskaya site
Site
location
Radiation budget components, W/m2
Heat budget components, W/m2
Short-wave solar radiation
Albedo
Effective
long-wave
radiation
Heat loss for
evaporation
(sublimation)
Heat flux to
rocks
Turbulent
heat transfer
total
reflected
adsorbed
Novolazarevskaya
11° E
70° S
125.0
26.7
98.3
0.2
61.1
1
10
–3
1.1
34.9
Mars South Pole cap
0° E
82.5° S
60.4
14.5
45.9
0.2
26.9
20.5
0.1
0.7
Mars North Pole cap
0° E
82.5° N
57.3
17.2
40.1
0.3
24.1
18.0
0.1
0.5
